Process and catalyst for hydrogen mediated saline hydride initiated anionic chain transfer polymerization

ABSTRACT

This invention relates to processes for forming hydrogen mediated saline hydride initiated anionic polystyrene distributions via novel polymerization conditions. This invention also relates to novel hydrocarbon soluble super active saline hydride catalyst and reagent compositions useful in conducting the hydrogen mediated saline hydride initiated polymerizations of this invention. This invention also relates to novel low molecular weight polystyrene polymer composition formed exclusively from styrene and molecular hydrogen as the monomers.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application, filed Jan. 19, 2023, is a Divisional of U.S. patent application Ser. No. 16/095,202 filed on Oct. 19, 2018, which is a national entry under 35 U.S.C. § 371 of Patent Cooperation Treaty Application No.: PCT/US2017/026340 filed Apr. 6, 2017, which claims priority to and the benefit of U.S. Provisional Application No. 62/325,149 filed Apr. 20, 2016, the entire contents and substance of all of which are hereby incorporated by reference as if fully set forth below.

TECHNICAL FIELD

This invention relates processes for forming hydrogen mediated saline hydride initiated anionic polystyrene distributions via novel polymerization conditions in which molecular hydrogen is a chain transfer agent and a Highly Active Saline Hydride (HASH) or a Super Active Saline Hydride (SASH) forms an anionic polymer chain initiating species by addition of saline hydride to an anionically polymerizable hydrocarbon monomer; all of which takes place in a very efficient to highly efficient catalytic cycle where the kinetic chain length distribution is mediated by hydrogen or otherwise set by the relative feed rate of hydrogen to monomer. This invention also relates novel hydrocarbon soluble super active saline hydride catalyst and reagent compositions useful in conducting the hydrogen mediated saline hydride initiated polymerizations of this invention. This invention also relates novel low molecular weight polystyrene polymer composition formed exclusively from styrene and molecular hydrogen as the monomers.

BACKGROUND OF THE INVENTION

Low molecular weight−M_(w)<<4000 Daltons—polystyrene compositions are useful in a variety of applications both in their end use such as polymer slip reagents (see EPO 741147) or as substrate precursor's for further synthetic derivatization. Such synthetic derivatization generally conducted through aromatic electrophilic substitution reactions (see: U.S. Pat. No. 8,217,120B2 “Functionalized styrene oligomers and polymers”). Anionic chain transfer polymerization of polystyrene provides an economic benefit due to the cost-effective efficient use of the anionic chain transfer catalyst when forming low molecular weight polystyrene compositions due to the use of substantially reduced amounts of organolithium reagents and other alkali earth metal regents used in forming the chain transfer initiator and catalyst. Accordingly, methyl benzene compounds (toluene). polymethylbenzene compounds (xylenes, mesitylene, durene, etc.) are excellent chain transfer agents for forming low molecular weight polystyrene compositions suitable for further synthetic elaboration. Such methyl benzene chain transfer agents owe in part their effectiveness because the pK_(a) of such compositions are generally at least one order of magnitude lower than that of a poly(styryl) anion's conjugate acid. Other alkyl substituted benzenes, ethylbenzene in particular, have been reported (EPO 741147) or at least suggested to be suitable organic chain transfer agents for forming anionic chain transfer styrene distributions using catalyst formed from potassium t-butoxide, butyllithium and TMEDA. Regardless of the method of forming an anionic chain transfer distribution, it is desirable to form low molecular weight polystyrene compositions free or essentially free of such organic chain transfer agents.

TABLE I Prior Art EPO 741147 Anionic Chain Transfer Styrene Polymerization w/ Ethylbenzene as the Chain Transfer Agent EPO 741147 Example# 1 2 3 4 5 6 7 Cyclohexane Diluent (ml) 0 1558 1558 1558 1558 1558 1558 g Cyclohexane/g Styrene 0 0.36 0.36 0.96 0.96 0.96 0.36 Mole K:Mole Li 1:1 1:1 1:1 1:1 1:1 1;1 1;1 Mole Styrene/mole 0.44 7.03 7.03 7.09 14.18 14.18 18.86 Ethylbenzene Mole Styrene/hr/mole 0.02 0.39 1.17 1.18 2.36 2.36 1.05 Ethylbenzene Mole Styrene/hr/mole 10.67 10.66 31.98 32.06 64.12 32.06 21.30 Lithium M_(n) 164 876 1212 932 2137 1736 596 M_(w) 262 19700 41800 1500 4830 3750 33300 M_(z) NR NR NR NR NR NR NR PD 1.60 22.50 34.50 1.61 2.26 2.16 55.90 Standard Deviation 127 4060 7013 728 2399 1870 4414 σ_(n) = (M_(w)M_(n)−M_(n) ²)^(1/2)

From the experimental details of EP 0 741 147 A1, as presented in Table I above, it can be seen by comparison of EP 0 741 147 Examples 2-7 that only Example 4 produced an anionic chain transfer styrenic reaction polymer distribution (ACTSR distribution) having limited breadth (standard deviation) and small polydispersity. Minor changes in the relative feed rates or charges as reported, or both simultaneously, resulted in ACTSR distributions having very large standard deviations and having polydispersity that increase significantly, and in some Examples, astronomically. Thus, it can be seen that from such experimental details, a very narrow and limited process window for producing distributions with narrow breath, i.e., small standard deviation σ_(n) is provided. Investigations of this prior art technology reveals that the process technology suffers from the undesirable formation of a catalyst composition of low or limited solubility in the hydrocarbon reaction medium. The process also relies on very slow relative feed rates conducted over long feed times (6 to 18 hours) in order to attempt to equilibrate living and dead polymer chains. The principle problem with ethylbenzene as a chain transfer agent is that the pK_(a) of ethylbenzene is of the same order of magnitude as that the conjugate acid of a poly(styryl) anion. It is desirable to have a new catalyst and anionic chain transfer polymerization conditions that can provide lower molecular weight polystyrene distributions under more economical use of reagents as well as shorter time periods and thus more productivity of the polymerization reactor.

Polymerization of styrene under a hydrogen atmosphere is known for Zeigler Natta polymerization of styrene (Murahashi, S.; Nozakura, S.; and Utsuhara Y. “Polymerization of Styrene with the Ziegler-Natta Catalysts in the Presence of Molecular Hydrogen.” Bulletin of the Chemical Society of Japan 1960 33 431). Additionally there is at least one report of for metallocene polymerization of styrene under a hydrogen atmosphere (Ref. 14: Tomotsu, N., Kuramoto, M., Takeuchi, M., & Maezawa, H. (1996). Metallocenes 1996, 96, 211.(i) Chien, J C W.; in Tomotsu, N., et al. “Syndiospecific Polymerization of Styrene.” Journal of Molecular Catalysis A: Chemical 1998 128.1 167.). In both polymerization chemistries formation of the hydrogenation product of styrene-ethylbenzene—is mentioned. Thus Utsuhara and coworkers reported that isotactic polystyrenes of low molecular weight could be obtained in the presence of hydrogen, although in addition to this there was found another reaction which is competitive to the polymerization reaction, i. e. hydrogenation of styrene to ethylbenzene. In both approaches—Ziegler Natta and metallocenes catalysis—to hydrogen mediation of styrene polymerization ethylbenzene is kinetically inert and represents an unrecoverable yield loss.

Deffieux and coworkers report the hydrogenolysis of poly(styrl)lithium distributions (50° C. Hz 1 atm) leading to the in situ formation of lithium hydride capable of reinitiating styrene anionic polymerization at 100° C. (Ménoret, S., Deffieux, A., & Desbois, P. “Initiation of retarded styrene anionic polymerization using complexes of lithium hydride with organometallic compounds.” Macromolecules, (2003) 36, 5988). Deffieux further reports that: “However, the slow addition of LiH to styrene with respect to propagation yields incomplete initiation.” Deffieux reports that with addition of an added organometallic reagent (n,sec-Bu₂Mg, or BuMgOBT or i-Bu₃Al) the solubility and reinitiation efficiency of the LiH is improved but the catalyst efficiency is only between 50% and 150%. Furthermore the bimetallic complex formed decreases the rate of termination and the half-life of the active or living poly(styryl)lithium species is greatly increased from 40 min for uncomplexed poly(styryl)lithium to 34 hours for the bimetallic complexed poly(styryl)lithium at 50° C. in cyclohexane and 1.1 atm H₂. In fact they report that it requires 50 atms H₂ to restore the half-life of the living poly(styryl)lithium species to 50 minutes. Deffieux and co-workers teach that soluble lithium hydride is a potential initiator of styrene polymerization:

-   -   “Lithium hydride, as long as it remains soluble, is a potential         initiator of styrene anionic polymerization, at least at 100°         C., even in nonpolar solvent. The efficiency of this initiator         is improved by complexation with organometallic derivatives         which first ensure its solubility and then reduce the styrene         propagation rate. When n,sec-Bu₂Mg is used as additive, Li—H         bonds are not the real initiating sites, the polymerization         proceeding after a ligand exchange between the two metal atoms.”     -   “At high temperature, H₂ acts as a chain transfer agent in         styrene anionic polymerization. However, to be efficient, its         concentration in the medium should be high in order to shift the         equilibrium toward the formation of metal hydride. This requires         high hydrogen working pressures.”         However Deffieux and coworkers require complexation of LiH with         Lewis acids such as dialkylmagnesium reagents, aluminum akyls         and/or alkylaluminum hydrides to solubilize the LiH. Such         complexed LiH reagents thus formed are not efficiently reduced         once used to polymerize styrene. Thus such Lewis acid complexed         poly(styryl)lithium chains are not efficiently reduced nor do         their reduction effectively regenerate a highly active or super         active form of LiH initiator.

It is documented in the literature that only two highly soluble Group 1 metal hydrides free of Lewis acid complexing agents are known (see: Stasch, A. and Fohlmeister, L. Aust. J. Chem. 2015, 68, 1190-1201.; and Liptrot, D. J., Springer Thesis: Group 2 Mediated Dehydrocoupling, Chapter 2. Group 1-Group 2 Bimetallic Alkyls and Hydrides, Springer International Publishing, 2016, pp. 41-61). These are: (1) the “super aggregate” [(t-BuOLi)₁₆(LiH)₁₇] generated via photolytic decomposition of a mixture of butyllithium lithium t-butoxide (Thomas, D. et.al., J. Am. Chem Soc. 1997, 119, 11998; and Thomas, D. et.al., Angew. Chem. Int. Ed. 1998, 37, 1537); and (2) Stash's hydrocarbon soluble LiH complex, [(DipNPPh₂)₄Li₈H₄] (Dip, 2,6-iPr₂C₆H₃), prepared by the application of phenylsilane to a reactive metal precursor (Stasch, A. Angew. Chem. Int. Ed. 2012, 51, 1930.) However this hydrocarbon soluble LiH reagent is not reactive enough to hydrolithiate the very active species diphenylacetylene or 1,1-diphenylethylene. Thus one of ordinary skill in the art would understand that [(DipNPPh₂)₄Li₈H₄] would not likely hydrolithiate a styrenic or other vinyl aromatic monomer and consequently would not initiate polymerization of such monomers. Stash also reports the formation of “initially clear solutions” of LiH/Li(pz) (pz=3,5-di-tert-butyl-1H-pyrazole) which turn milky likely due to formation of colloidal LiH. Such “initially clear solutions” are prepared by treating 3,5-di-tert-butyl-1H-pyrazole (pzH) with more than one equivalent of n-butyllithium in aromatic or aliphatic solvents, followed by addition of phenyl- or diphenylsilane to convert the excess alkyllithium groups to hydrides. Stash has prepared the first NaH complex [(pz)₆Na₇H] by the same synthetic strategy as the LiH/Li(pz) methodology again using the sterically demanding pyrazolate ligand (pz) by the reaction of [Na(pz)], [Na(n-Bu)] and diphenylsilane in aromatic solvents. The application of the same synthetic strategy used to produce [(pz)₆Na₇H] to form a KH hydride analogue resulted only in the formation of crystalline polymeric [K(pz)]. Thus a stable aliphatic and/or cycloaliphatic and/or aromatic hydrocarbon soluble monometallic, bimetallic or polymetallic alkali (Group 1) metal hydride formed directly from molecular hydrogen, H₂, is heretofore unknown.

In their publication (Stasch, A. and Fohlmeister, L. Aust. J. Chem. 2015, 68, 1190-1201) teach the following:

-   -   “Well-defined hydride complexes purely of Group 1 metals are         very rare and are in fact only known for lithium and sodium so         far . . . . Most isolated compounds involving alkali metals and         hydridic hydrogen centres are mixed-element systems and are best         described as ‘ate’-type complexes in which the strongest         interaction of the hydride ligand is with the non-alkali metal         centre or metalloid . . . This makes the majority of these ‘ate’         complexes covalent hydride complexes. The most prominent         examples in this compound class are perhaps LiAlH₄, NaBH₄, and         other related commercial derivatives such as L-selectride®,         N-selectride®, and K-selectride® (lithium, sodium, potassium         tri-sec-butyl(hydrido)borate), or derivatives with sterically         demanding ligands.” emphasis added.

In contrast to covalent hydrides, saline, or ionic, hydrides are defined by the presence of hydrogen as a negatively charged ion, H⁻, in combination with an alkali metal or alkaline earth metal. With regard to the addition of other saline hydrides to styrene with concomitant polymerization Deffieux and coworkers provide the following background (ibid):

-   -   “To the best of our knowledge, very few papers deal with anionic         polymerization of vinylic monomers initiated by metal hydrides.         Williams briefly mentioned one styrene polymerization experiment         initiated by NaH in hexane at 25° C. However, the initiation         efficiency was very low and the conversion reached only 90%         after 3 days.”

Liao and coworkers reported a form of highly active alkali metal hydrides having nanometric (≈20 nm) particle size distributions (Liao, S.; et.al. Journal of Molecular Catalysis, 1993, 84, 211.) In this paper Liao reports formation of highly active saline hydrides (HASH) from the corresponding alkali metal and hydrogen (1 atm) in THF (40° C.) catalyzed by TiCl₄ and naphthalene. Complete conversion to the saline hydride required 2 hours for LiH*, 4 hours NaH* and 28 hours for KH* (the * denoting highly active or super active hydride). These nanometric saline hydrides were found to have some utility in the dechlorination and debromination of certain arylhalides. They were also reported to be active as co-catalyst for the hydrogenation of olefins such as 1-hexene when used in certain transition metal complexes. Turnover frequencies in the range of 0.003 to 45.3 s⁻¹ were reported. Thus highly active alkali metal hydrides (50-300 mol) when used in conjunction of a transition metal catalyst (1 mol) only reduce olefins, no disclosure of polymerization or even dimerization of the olefin is made.

Other applications of nanometric size alkali metal hydrides were later reported by Liao and coworkers (Liao, S.; et.al. Synth. Comm. 1997, 27 3977.) Such applications include the reduction of carbonyl carbon to aldehydes and/or alcohols of benzaldehyde, methyl benzoate, acrolein and the methyl and n-butyl ester of acrylic acid. The reactions were conducted in refluxing THF using a stoichiometric excess of highly active saline hydride—either as NaH* or as KaH*— and reactions times of 0.25 to 15 hours. Of particular interest are the reduction of acrolein (0.3 hour) and methyl acrylate (0.25 hour) with NaH* to yield allyl alcohol in 97% and 96% yield respectively. In another publication Liao and co-workers report that heat treated nanometric LiH, NaH and KH complexed with Cp₂TiCl₂, CP₂TiCl₂-MH (M=Li, Na or K), can be used as a catalyst to hydrogenate either styrene (M=Li or Na) or octene (M=K). Nanometric KH with Cp₂TiCl₂ under one atmosphere H₂ did not hydrogenate styrene instead initiated polymerization to form very high molecular weight (MW) polystyrene (M_(w)=200,000) with a wide range of melting points T=160-180° C. It was further found that nanometric KH alone polymerized styrene, one of ordinary skill in the art would understand that such high MW anionic polystyrene (APS) compositions are the result of inefficient initiation of polymerization thus resulting in formation of only very few living polymer chains which rapidly incorporate the styrene monomer at the expense of the remaining insoluble nanometric KH.

Zhang and co-workers report highly active catalysts for the hydrogenation of styrene (2 ml) in toluene (9 ml) under hydrogen atmosphere at −17° C. to 42° C. (Zhang, M.; et.al. Catal Lett 2008, 124, 146.). The highly active catalyst was formed from nanometric sized sodium hydride (20 mg, 8.7×10⁻⁴) and 12 different Lewis base free titanocene complexes (0.5 mL of 4×10⁻⁴ mol/L i.e. 2×10⁻⁷ mol)−NaH*/Ti=4350). Uptake of hydrogen was not observed in two other examples where the titanocene complex contained a coordinating oxygen (ether) or nitrogen (tertiary amine) species. Despite the large excess of NaH* to the titanocene catalyst, no report or even mention is made of the polymerization of styrene much less any form of chain transfer chemistry.

The preparation of super active—extremely finely divided—forms of lithium, sodium and potassium hydrides were reported by Schleyer and co-workers (Schleyer, P. v. R.; et.al. J. Org. Chem. 1987. 52, 4299; and Schleyer, P. v. R.; et.al. Angew Chem Int. Ed. Engl. 1986 25 465.) The preparation of these super active saline hydrides (SASH) as a fine suspension entailed the hydrogenation of the corresponding alkali metal alkyls in the presence of N,N,N′,N′-tetramethylethylenediamine (TMEDA) in hexanes. Formation of super active LiH* was conducted between 30 and 35° C., super active NaH* was prepared under cryogenic conditions (−10° C. to-15° C.), and super active KH* was reported to be formed at −20° C. to −25° C. The application of the hydrides to organic synthesis was explored by Schleyer and reported in the above cited open literature papers. Most of the synthetic reactions (metalations, additions and reductions) were conducted under cryogenic conditions with temperatures as low as −90° C. with a few reactions conducted between room temperature and 50° C. There were also no disclosures in Schleyer to use the hydrides for polymerization of styrenic, vinyl aromatic or conjugated diene monomers much less hydrogen mediation of such polymerization processes.

Harder and coworkers have reported that styrene can be catalytically hydrogenated (20° C., 20 atmospheres H₂, 15 hours in benzene) with 2.5 mole % of the organocalcium catalyst, [DIPPnacnacCaH·THF]₂ initially formed from phenylsilane, (see. Harder, S., Speilman, J., Buch, F. Angew. Chem. 2008, 120, 9576 also published as Angew. Chem. Int. Ed. 2008, 47, 9434.) The hydrogenation produced ethylbenzene in 85% yield along with a 15% yield of oligomers comprised mostly of styrene dimer with traces of styrene trimers and oligomers. Harder further reports 1,1-diphenylethene is reduced at a low conversion to yield 14% Ph₂CHCH₃ and 7% dimer in a catalyst formed from 5 mole % butyllithium/TMEDA complex at 20° C., 20 atmospheres H₂, 15 hours in benzene. With regard to this reaction the authors make the following statement:

-   -   “The reaction catalyzed by commercially available nBuLi/TMEDA         proceeded only to low conversion . . . suggesting that, at lower         H₂ pressures, the heavier alkaline-earth metal complexes are the         more efficient catalysts.”

Tetrahydrofuran soluble forms of magnesium hydride were produced by Ashby and coworkers from ortho-substituted (2,6-dimethyl- and 2,6-di-isopropylphenoxides) aryloxymagnesium reagents and an active form of solid magnesium hydride. Tetrahydrofuran insoluble forms of magnesium hydride resulted from alkoxymagnesium reagents and the solid magnesium hydride reagent (see Ashbey, E. C., Goel, A. B., Lin, J. J. Tetrahedron Letters, 1977, 3133.) Ashby also reported the formation of tetrahydrofuran soluble dialkylaminomagnesium hydrides a series of bulky dialkyl and alkylsubstituted cycloalkyl secondary amines and an active form of solid magnesium hydride. Said active form of magnesium hydride was prepared by the reduction of dimethylmagnesium with LiAlH₄ in diethyl ether. Thus the bulky dialkyl and alkylsubstituted cycloalkyl secondary amines are reacted with dimethylmagnesium to form the bis(dialkylamino)magnesium compounds which were in turn reacted in THF with the active form of magnesium hydride (see Ashbey, E. C., Goel, A. B., Lin, J. J. J. Or. Chem., 1978, 43, 1564. Such aminomagnesium hydrides are likely to initiate polymerization by the addition of amide to the monomer and result in undesired amine functionality in the resulting polymer distribution.

Michalczyk report the formation in ethereal or hydrocarbon solvents in the presence of “appropriate ligands” the formation of a precipitated form of magnesium hydride MgH₂L_(x). Such appropriate ligands included tetrahydrofuran, ethylene glycol dimethyl ether, and TMEDA. The reducing agent employed was phenylsilane (see Michalczyk, M. J. Organometallics, 1992, 11, 2307). In a recent review entitled “Molecular Early Main Group Metal Hydrides: Synthetic Challenge, Structures and Applications” Harder reviews the state of the art of the controlled synthesis of well-defined Group 1 and Group 2 metal hydrides. In general such hydrides have been prepared by the methods outlined above which include: photo-degradation; reactions of active hydrides to form “ate-complexes” such as the aryloxymagnesium hydride as well as the dialkylaminomagnesium hydrides reported by Ashby; Harder's [DIPPnacnacCaH·THF]₂ initially formed from phenylsilane; and Stach's soluble lithium hydride complex formed from phenylsilane. Additionally Harder reviews a host of hydrides formed from the thermal decomposition of magnesite complexes [(iPr₂N)₃Mg⁻]M⁺ (M⁺=Na⁺, K⁺). A common feature of all approaches to forming soluble saline hydride compositions is the use of bulky (usually isopropylated ligands) to achieve solubility. In all cases except for the poorly catalytic species formed during the hydrogenation of styrene to ethylbenzene (85% yield) such as the example using [DIPPnacnacCaH·THF]₂ (which again was initially formed from phenylsilane) the saline hydride complexes were formed from some other reagent other than molecular hydrogen. Only Scheyer's insoluble forms of super active saline hydrides (SASH) are formed from molecular hydrogen and as the initial reagent.

Accordingly, the prior art does not disclose the use of either a highly active saline hydride (HASH) or a super active saline hydride (SASH) species for anionic-chain transfer polymerization of vinyl heteroaromatic monomers and/or vinyl aromatic monomers such as a styrenic monomers and/or conjugated diene monomers or other olefinic hydrocarbon anionically polymerizable monomers. The inventor has discovered that the use of these hydrides can catalyze a hydrogen mediated saline hydride initiated polymerization (HMSHIP) process. This invention provides a process for the efficient anionic chain transfer polymerization of vinyl aromatic monomers under ambient temperatures (e.g., about 20° C. to 100° C.) where hydrogen is the principal or sole chain transfer agent. Said process can be conducted at relatively low to very low hydrogen pressures partial pressures. Furthermore the inventor has discovered that the novel polymerization catalysts of this invention provide low molecular weight anionically polymerized styrene distributions comprised solely of styrene.

Numerical Terms

The efficiency (Eff_(CT)) of an anionic chain transfer process is given by the expression:

Eff _(CT⋅) =M _(n Th) /M _(n exp);

where M_(n Th) the theoretical number average molecular weight, and the term M_(n exp) is the number average molecular weight obtained in the actual run or process.

A brief resume of parameters used to describe molecular weight distributions and the equations that define them are presented in Table 2. (A. Rudin, The Elements of Polymer Science and Engineering, Academic Press, Orlando, 1982, pp. 54-58). The number average DP (DP_(n)) is calculated using M_(n) as 100% polystyrene compositions.

TABLE 2 Parameter Equation DP_(n), Number average degree DP_(n) = (M_(n) − 2)/104 (for a polystyrene of polymerization distribution) M_(n), Number average M_(n) = (Σ M_(i)n_(i)) molecular weight M_(w), Weight average M_(w) = [(Σ M_(i) ²n_(i))/M_(n)] molecular weight M_(z), z-Average molecular M_(z) = (Σ M_(i) ³n_(i))/ΣM_(i) ²n_(i) weight PD, Polydispersity Index PD = (Σ M_(i)n_(i))/[(Σ M_(i) ²n_(i))/M_(n)] (also PDI) Variance V = (M_(w)M_(n) − M_(n) ²) Standard Deviation, σ_(n) σ_(n) = √{square root over ((M_(w)M_(n) − M_(n) ²))} Skewness, _(n)U₃ _(n)U₃ = M_(z)M_(w)M_(n) − 3M_(n) ²M_(w) + 2M_(n) ³ Asymmetry, _(n)α₃ _(n)α₃ = (M_(z)M_(w)M_(n) − 3M_(n) ²M_(w) + 2M_(n) ³)/σ_(n) ³

SUMMARY OF THIS INVENTION

The hydrogen mediated saline hydride initiated polymerization (HMSHIP) processes of this invention feature: a) the novel ability of soluble saline hydride species to add rapidly to a vinyl aromatic or a conjugated diene monomer to form an initiating species; b) the novel high efficiency in which the addition of the saline hydride species to monomer takes place and thus allows competition between the re-initiation step to compete with the propagation reaction step to grow the active transient living poly(styryl) anion chains thus maintaining a constant number of active growing chains; and c) the capacity of chain transfer from hydrogen under the mild and novel process conditions to terminate such living poly(styryl) anionic species and regenerate the saline hydride in a form capable of effectively reinitiating the polymerization process. Without such features the chemical process would otherwise either produce mainly reduced monomer on one extreme or high molecular weight polymer at the other.

The present invention relates to a process for anionic chain transfer polymerization comprising feeding vinyl heteroaromatic monomers and/or vinyl aromatic monomers, preferably a styrenic monomer, and/or conjugated diene monomer under an atmosphere comprising molecular hydrogen to a reactor vessel containing a reaction mixture of an inert ethereal solvent and an alkali metal or alkali metal alloy.

The present invention also relates to a process for anionic chain transfer polymerization comprising feeding vinyl aromatic monomer, preferably a styrenic monomer, and/or conjugated diene monomer under an atmosphere comprising molecular hydrogen to a reaction mixture in a reactor vessel, wherein said reaction mixture was formed from (a) an organolithium compound; (b) a polytertiaryamine compound; (c) a metal alkoxide, wherein said alkoxide is one or more alkali metal alkoxide, or a magnesium alkoxide; (d) optionally an aromatic hydrocarbon having at least one C—H covalent bond pK_(a) within the range of 2.75 pK_(a) units above that of the pK_(a) of toluene to −4.30 pK_(a) units below the pK_(a) of toluene; and (e) a hydrocarbon solvent having a pK_(a) greater than H₂.

The present invention also relates to a hydrocarbon soluble monometallic, bimetallic or polymetallic SASH catalyst composition formed from a reaction medium comprising: (a) molecular hydrogen; (b) an organolithium compound and/or an organomagnesium compound; (c) a polytertiaryamine compound; (d) an alkoxide, wherein said alkoxide is one or more alkali metal alkoxide(s), or a magnesium alkoxide (e optionally an aromatic hydrocarbon having at least one C—H covalent bond pK_(a) within the range of 2.75 pK_(a) units above that of the pK_(a) of toluene to −4.30 pK_(a) units below the pK_(a) of toluene; and (f) a hydrocarbon solvent; wherein the aromatic hydrocarbon and hydrocarbon solvent may be the same or different.

DETAILED DESCRIPTION OF THE INVENTION Glossary

It is to be understood and appreciated that the term “polymer” as used anywhere herein, including the claims, refers to the term “polymer” as defined in the context of the OECD definition of “polymer”, which is as follows:

-   -   “A chemical substance consisting of molecules characterized by         the sequence of one or more types of monomer units and         comprising a simple weight majority of molecules containing at         least three monomer units which are covalently bound to at least         one other monomer unit or other reactant and which consists of         less than a simple weight majority of molecules of the same         molecular weight. Such molecules must be distributed over a         range of molecular weights wherein differences in the molecular         weight are primarily attributable to differences in the number         of monomer units.”

The terms “organolithium (active)” and “active organolithium” (abbreviated as Li active) means the amount of organolithium compound charged above the amount of organolithium compound needed to titrate any protic reagent as well as any protic impurity species such as water, and/or alcohol and/or a primary or secondary amine. Though we wish not to be bound by theory it is considered to be that the molar amount of active organolithium is equal to the molar amount of saline hydride formed on a 1:1 basis.

Protic when in combination with the term species, or reagent, or solvent or impurity means a chemical species having a covalently bonded proton (H⁺) with a pK_(a) below that of H₂ under the conditions of the chemical processes of this invention (see Buncel, E., Menon, B J. Am. Chem. Soc., 1977, 99, 4457: “Carbanion mechanisms. 6. Metalation of Arylmethanes by Potassium Hydride/18-Crown-6 Ether in Tetrahydrofuran and the Acidity of Hydrogen”).

“HASH” means a Highly Active Saline Hydride formed from an alkali metal or alkali metal alloy in an ethereal solvent under an atmosphere comprising molecular hydrogen.

“SASH” means a Super Active Saline Hydride formed from (a) molecular hydrogen; (b) an organolithium compound; (c) a polytertiaryamine compound; (d) an alkoxide, wherein said alkoxide is an alkali metal alkoxide, or a magnesium alkoxide; (e) optionally an aromatic hydrocarbon having at least one C—H covalent bond pK_(a) within the range of 2.75 pK_(a) units above that of the pK_(a) of toluene to −4.30 pK_(a) units below the pK_(a) of toluene; and in (f) a hydrocarbon solvent; wherein the aromatic hydrocarbon and hydrocarbon solvent may be the same or different (the reference pK_(a) of toluene is that of the methyl protons i.e. one of the hydrogen atoms of the carbon hydrogen (—CH₃) bonds, and not that of the ring protons nor any secondary ionization. See in this connection Gau, G. Marques, S. J. Am. Chem. Soc., 1976, 98, 1538: “Acidities of Alkylarenes from the Equilibriums of their Sodium Salts”).

The term “molecular hydrogen” means H₂ as ¹H₂ but can also include the isotopes of hydrogen ²H₂ or ³H₂ either as mixtures of the isotopes or enriched in a particular isotope whether in the gas state in the vapor space or dissolved in the condensed phase.

The term “diene” (or diolefin) means an unsaturated hydrocarbon that contains two carbon double bonds. A conjugated diene is a diene where the two double bonds are separated by a single bond and hence have overlapping and shared molecular orbitals.

The term “inert ethereal solvent” means a solvent comprising at least one ether solvent which does not react with alkali metal and/or the catalyst and/or any reactive intermediate(s) derived therefrom in such a manner that the ethereal solvent is degraded or converted into another reagent deleterious to the chemistry or process. However the inert ethereal solvent may act as a Lewis base and hence form a complex with the alkali metal and/or the catalyst and/or any reactive intermediate(s) derived therefrom.

The term “alkali metal alloy” means a metal alloy of at least two metals wherein at least one of which is an alkali metal however such an alkali metal alloy can be comprised of two alkali metals such as NaK or NaK₂ and may have such alkali metals dissolved or in some physical combination with the alloy.

The term “electron transfer entraining agent” is a neutral organic molecule such as but not limited to naphthalene or biphenyl which readily undergoes reduction via single electron transfer from the alkali metal or alkali metal alloy forming a radical anion and then in turn can transfer the electron to a polymerizable monomer such as styrene and thereby is re-oxidize to the neutral organic molecule.

The term “and/or” means singular or a combination. For example, “A and/or B” means “A” alone, “B” alone, or a combination of A and B.

The term “with or without” means singular or in combination. For example A with or without B means “A” alone or a combination of A and B.

The term “organolithium compound” means an organic group bonded to a lithium atom. Non-limiting examples of organic groups may be aliphatic (e.g., an alkyl group), cycloaliphatic (e.g., cycloalkyl), vinyl group, allylic group, benzylic group, an aromatic group (e.g., phenyl) or a polystyryllithium.

The “term polytertiaryamine promoter” means a compound containing at least two tertiary amine groups that promotes or activates the formation of the hydride catalyst during the HMSHIP process. Non-limiting generic formulae for such polytertiaryamines would include:

where R′ and R″ are independently organic groups capable of forming bonds with two or more amines and R¹, R², R³, R⁴, and R⁵ are independently organic groups which may also be further substituted by other tertiary amines, and the index value n is independently a whole number equal to or greater than 0 (i.e. n=0, 1, 2, 3 . . . ). It should be understood that when n=0 than the group within the parentheses does not exist and the structure is intended to mean that the chemical bond is between the two groups that intersect the two sides of the parentheses. Thus polyteriary amine structure 2 becomes structure 4 when n=0.

The term “alkali or alkaline earth metal alkoxide” means an alkoxide with the generic formula MOR, where M is an alkali metal, or magnesium or calcium metal, O is oxygen and R is an organic group such as alkyl, cycloalkyl. benzyl or aromatic group. They are typically formed by the reaction of the metal, metal hydride or metal alkyl with a compound containing an alcohol group. For the purpose of distinction catalyst forms an “alkali metal alkoxide” does not contain an ether or tertiary amine moiety as a part of a functional group in its chemical structure. Catalysts formed from these reagents have distinctly different solubility's, reactivity's and selectivity's and thus should in no way be equated.

DESCRIPTION

The present invention relates a process of conducting hydrogen mediated saline hydride initiated polymerizations (HMSHIP) of anionically polymerizable hydrocarbon monomers, catalyst compositions for conducting such a process and under certain preferred conditions the formation of novel and beneficial low molecular weight anionic chain transfer polymer distributions. The process features feeding at least one anionically polymerizable hydrocarbon monomer to a suitable solvent containing an active and generally soluble saline hydride catalyst under an atmosphere comprising molecular hydrogen wherein chain transfer from molecular hydrogen is a significant component of the mechanism that determines the kinetic chain length (v) distribution and hence the number average molecular weight (M_(n)) of the resulting product distribution.

The present invention also relates a process of conducting hydrogen mediated saline hydride initiated polymerizations which features feeding at least one anionically polymerizable vinyl heteroaromatic monomer to a suitable solvent containing an active and generally soluble saline hydride catalyst under an atmosphere comprising molecular hydrogen wherein chain transfer from molecular hydrogen is a significant component of the mechanism that determines the kinetic chain length (v) distribution and hence the number average molecular weight (Mn) of the resulting product distribution.

One embodiment of the present invention relates to a process for anionic polymerization of vinyl aromatic monomers such as a styrenic monomer (i.e., styrene) using active saline hydrides. A general, non-limiting, representation of a styrene polymer mechanism is shown below. In this general representation of the anionic polymerization process, MH* denotes an activated form of a saline hydride for the saline hydride metal in HASH or SASH. The terms k_(MH*), k_(i), k_(p), and k_(r), represent the rate constants for MHI* addition, chain initiation, chain propagation and reductive chain transfer steps respectively, Saline hydrides—also called ionic hydrides—include hydrides of alkali metals and alkaline earth metals. Thus M can be or include one or more of lithium, sodium, potassium, rubidium, cesium, magnesium or calcium.

Under the conditions of this novel anionic chain transfer polymerization reaction either a HASH or a SASH catalyst is used in the reduction of an active or living poly(styryl) anion by molecular hydrogen. This reductive chain transfer yields a discrete dead polystyrene chain and regenerates the active catalyst species. Repetition of the process through many catalytic cycles of the 4 steps: 1) MH* addition to styrene; 2) polymer chain initiation forming a mono-adduct; 3) polymer chain propagation and 4) chain transfer to form a discrete dead polymer chain; provides an anionic chain transfer polystyrene distribution of dead polymer chains of characteristic molecular weights (M_(n), M_(w), and M_(z)), polydispersity index, standard deviation and asymmetry. The processes of this invention are highly efficient with catalyst efficiencies typically in the range

The use of the optional aromatic hydrocarbon and its incorporation into the resulting polymer distribution is outlined in the chemical equations [i.e. the sequence beginning with (6) followed by (2) and completed by (3)] above. The equations below use the non-limiting examples of styrene for the monomer and ethylbenzene for the aromatic hydrocarbon. It should be understood that with or without ethylbenzene present from the start, a portion of styrene is reduced to ethylbenzene during the course of an HMSHIP process when styrene is the monomer. However the ethylbenzene formed can be kinetically active and can reenter the chain transfer chemistry when the HMSHIP process is conducted above about 50° C. Under such conditions the hydrogenated styrenic monomer (ethylbenzene) can be kinetically active as a chain transfer agent forming the identical and indistinguishable anionic chemical species as is formed when in this example MH* is added to the styrenic monomer when that monomer is styrene.

If one or more other chain transfer agents are used as the solvent(s) then a portion of the distribution of dead polymer chains may have incorporated the added chain transfer agent(s) (depending on the relative pK_(a) of the chain transfer agent and the nature of the saline hydride catalyst). For a process where the recovered styrenic monomer reduction products are recycled directly back to the process, the product distribution of dead polymer chains is comprised solely of a collection of discrete styrenic polymer chains having an initiating hydride and a terminating proton derived from molecular hydrogen.

Because one key feature of this invention is the highly efficient addition of a HASH or SASH to styrene or other styrenic monomers and subsequent rapid initiation (chemical equations 1 and 2), the number average molecular weight distribution M_(n) of polymer distributions producible by this invention can be expressed in terms of a kinetic chain length (υ). The number average degree of polymerization DP _(n)=ψ and is given by the ratio of the rate of the reactions that make the polymer grow divided by the rate of the reactions that stop growth. Though we wish not to be bound by theory DP _(n) can be expressed in terms of the chain transfer constant C_(r) _(Hsty) ⁽⁻⁾ for the reduction of the polymer initiation species (i.e. is the addition product of the saline hydride to the monomer denoted as Hsty⁽⁻⁾⁾ and both the chain transfer involving hydrogen

(C_(tr_(H₂)))

and chain transfer involving ethylbenzene (C_(tr) _(EB) ). The kinetic chain length (υ) is expressed for certain embodiments of this invention by Equation (IV) below. From Equation (IV) at increased styrene concentrations [sty] (faster styrene feed rates) and reduced H₂ concentration [H₂] (reduced partial pressure or mass transfer) and reduced ethylbenzene concentration [EB], the kinetic chain length u becomes large. Conversely at decreased styrene concentrations (via slower styrene feed) and increased H₂ concentration (via increased partial pressure or mass transfer) and increased ethylbenzene concentration, the kinetic chain length u becomes small.

$\begin{matrix} {{\overset{\_}{DP}}_{n} = \frac{{k_{p}\left\lbrack {Hsty}_{n}^{-} \right\rbrack}\lbrack{sty}\rbrack}{\left( {{{k_{r_{EB}}\left\lbrack H_{2} \right\rbrack}\left\lbrack {Hsty^{( - )}} \right\rbrack} + {{k_{{tr}_{H_{2}}}\left\lbrack H_{2} \right\rbrack}\left\lbrack {Hsty}_{n}^{-} \right\rbrack} + {{k_{{tr}_{EB}}\left\lbrack {EB} \right\rbrack}\left\lbrack {Hsty}_{n}^{-} \right\rbrack}} \right)}} & (I) \end{matrix}$ $\begin{matrix} {\psi^{- 1} = {\left( {\overset{\_}{DP}}_{n} \right)^{- 1} = \frac{{{k_{r_{{Hsty}^{( - )}}}\left\lbrack H_{2} \right\rbrack}\left\lbrack {Hsty}^{-} \right\rbrack} + {{k_{{tr}_{H_{2}}}\left\lbrack H_{2} \right\rbrack}\left\lbrack {Hsty}_{n}^{-} \right\rbrack} + {{k_{{tr}_{EB}}\lbrack{EB}\rbrack}\left\lbrack {Hsty}_{n}^{-} \right\rbrack}}{{k_{p}\left\lbrack {Hsty}_{n}^{-} \right\rbrack}\lbrack{sty}\rbrack}}} & ({II}) \end{matrix}$ $\begin{matrix} {\psi^{- 1} = {\frac{{k_{r_{Hsty^{( - )}}}\left\lbrack H_{2} \right\rbrack}\left\lbrack {Hsty}^{-} \right\rbrack}{{k_{p}\left\lbrack {Hsty}_{n}^{-} \right\rbrack}\lbrack{sty}\rbrack} + \frac{{k_{{tr}_{H_{2}}}\left\lbrack H_{2} \right\rbrack} + {k_{{tr}_{EB}}\lbrack{EB}\rbrack}}{k_{p}\lbrack{sty}\rbrack}}} & ({III}) \end{matrix}$ $\begin{matrix} {\psi^{- 1} = {{C_{r_{Hsty^{( - )}}}\frac{\left\lbrack H_{2} \right\rbrack\left\lbrack {Hsty}^{-} \right\rbrack}{\left\lbrack {Hsty}_{n}^{-} \right\rbrack\lbrack{sty}\rbrack}} + {C_{{tr}_{H_{2}}}\frac{\left\lbrack H_{2} \right\rbrack}{\lbrack{sty}\rbrack}} + {C_{{tr}_{EB}}\frac{\lbrack{EB}\rbrack}{\lbrack{sty}\rbrack}}}} & ({IV}) \end{matrix}$

Further Detailed Description of this Invention

The anionically polymerizable hydrocarbon monomers can include one or more vinyl aromatic monomers especially styrenic monomers, conjugated diene monomers and olefin monomers. Preferably, the vinyl aromatic monomer is a styrenic monomer such as styrene, or alkylated styrene monomers such as such as the o- m-, and p-, isomers of methyl styrene, p-isopropylstyrene, 2,4-diethylstyrene, o-ethylstyrene, 3,5-di-isobutylstyrene, 2,6-dimethyl styrene, 2-ethyl-4-methylstyrene and combinations thereof. For forming linear polymeric microstructures free of branching molecular architectures, styrene is the preferred vinyl aromatic monomer. Alkylated styrene monomers under the process conditions will themselves behave as chain transfer agents and result in some degree of branching and potential cross linking. Divinyl aromatic monomers such as divinylbenzene can also be used as co-monomers however branching and crosslinking can occur.

Non-limiting examples of conjugated diene monomers are 1,3-butadiene, isoprene, 1,3-pentadiene, 2,3-dimethyl-1,3-butadiene and 1,3-hexadiene.

Non-limiting examples of olefin monomers can include ethylene, propene, butene, pentene, hexene, octene and the like as well as a non-conjugated di-olefin such as 4-vinyl-1-cyclohexene. Such olefinic monomers form telomer distributions under the HMSHIP process conditions.

One embodiment of the present application relates to a process for hydrogen mediated anionic chain transfer polymerization (hereinafter: HASH catalyst process) comprising feeding a styrenic monomer and/or other vinyl aromatic monomer and/or conjugated diene monomer under an atmosphere comprising molecular hydrogen to a reactor vessel containing a reaction mixture of an inert ethereal solvent and an alkali metal or alkali metal alloy ideally as a suspended dispersion. The product of which when the monomer is solely styrene is designated as a HASH PS distribution.

Non-liming examples of inert ethereal solvent are tetrahydrofuran, cyclopentyl methyl ether, di-tert-butyl ether, diethyl ether, diethylene glycol diethyl ether, diglyme, dimethoxyethane, 1,4-dioxane, ethyl tert-butyl ether, methoxyethane, methyl tert-butyl ether, 2-methyltetrahydrofuran, and tetrahydropyran.

Non-limiting and preferred examples of alkali metal and/or mixtures of alkali metals and/or alkali metal alloys as dispersions of lithium, and/or sodium, and/or potassium, and/or rubidium and/or cesium; and dispersions formed from sodium potassium alloys such as NaK and/or NaK₂.

One embodiment of the HASH catalyst process is where the styrenic monomer is styrene, the ethereal solvent is tetrahydrofuran and the sodium potassium alloy is NaK₂. In addition, the partial pressure of hydrogen is maintained at pressures between about 2.5 Bar to about 10 Bar

The HASH catalyst process above may also contain in the reaction mixture an electron transfer entraining agent. Non-liming examples of electron transfer entraining agent are biphenyl, naphthalene, or other preferably unsubstituted—to avoid incorporation in the polymer composition—conjugated aromatic hydrocarbons, or fused ring aromatic hydrocarbons.

In one embodiment of the present application, the ethereal solvent and alkali metal or alkali metal alloy are initially charged into the reactor vessel and agitated using high shear high speed mixing (high shear impeller with tip speed>15 ft/s or 4.5 meter/s) to create and maintain an alkali metal or metal alloy dispersion for as long as metallic (Li⁰, Na⁰, K⁰, Cs⁰) alkali metal is present and at a temperature above its melting point.

The partial pressure of hydrogen employed in the above HASH catalyst process is maintained at pressures between about 1.0 to about 20.0 Bar, or about 1.5 to about 12.0 bar, or about 2.5 to about 10.0 Bar or about 3.0 to about 7.0 Bar

The molar ratio amount of alkali metal or alkali metal alloy to styrenic and/or conjugated diene monomer may range of about 1:10 to about 1:100 or about 1:15 to about 1:50.

The temperature of the reaction mixture and/or process is maintained in the range of about 20° C. to about 100° C., and preferably in the range of about 40° C. to about 80° C.

As mentioned above, the agitation in the reactor vessel should be at least sufficient to maintain a substantially homogeneous concentration profile of the styrenic monomer in the inert ethereal solvent and to efficiently transport Hz from the gas or vapor phase to the condensed phase.

Additionally, it is desirable that when the alkali metal is potassium, sodium, or an alloy of potassium and sodium to employ high shear mixing to create and maintain a dispersion of the initially charged alkali metal at a temperature sufficiently high to melt the alkali metal or metal alloy if the metal or metal alloy is not already in a liquid state above its melting point.

Upon completion of the reaction, as indicated, for example, by rapid reduction in the process temperature at constant heat flux and/or the termination of uptake of Hz, the reaction mixture is placed under increased hydrogen pressure and then transferred to a wash reactor for quenching and water washing. The wash reactor may be previously charged with a high boiling solvent such as ethylbenzene with little or no water. To aid in recovery of solvent, it is preferred to distill the ethereal solvent prior to contacting the reaction mixture with water. The quench can be conducted at ambient temperatures and employs a minimum of a protic solvent such as isopropyl alcohol which is fed carefully with time to allow hydrogen to safely vent from the reactor. The product is water washed to remove alkali metal salts. The high boiling solvent may be separated and recovered from the washed reaction mixture, whereby the last traces of water are also removed azeotropically from the reaction mixture. This separation operation is continued until most of the solvent and the monomer reduction product (for styrene the reduction product is ethylbenzene) is removed. Alternatively the catalyst can be quenched in the polymerization reactor by slow addition of the protic quenching agent. Upon completion of the quench, the quenched reaction mixture is transferred to the wash reactor and the work up is as described above.

Another embodiment of the present application relates to a process for hydrogen mediated anionic chain transfer polymerization comprising feeding a styrenic monomer and/or other vinyl aromatic monomer and/or conjugated diene monomer under an atmosphere comprising molecular hydrogen to a reactor vessel containing reaction mixture of a hydrocarbon solvent and a hydrocarbon soluble saline hydride catalyst. The soluble saline hydride catalyst is a SASH catalyst

Another embodiment of the present application relates to a process for anionic chain transfer polymerization comprising feeding vinyl aromatic monomer, preferably a styrenic monomer, and/or conjugated diene monomer under an atmosphere comprising molecular hydrogen to a reaction mixture in a reactor vessel, wherein said reaction mixture was formed from (a) an organolithium compound; (b) a polytertiaryamine compound; (c) a metal alkoxide, wherein said alkoxide is one or more alkali metal alkoxide, or a magnesium alkoxide; (d) optionally an aromatic hydrocarbon having at least one C—H covalent bond pK_(a) within the range of 2.75 pK_(a) units above that of the pK_(a) of toluene to −4.30 pK_(a) units below the pK_(a) of toluene; and (e) a hydrocarbon solvent having a pK_(a) greater than Hz. The aromatic hydrocarbon and hydrocarbon solvent may be the same or different.

The partial pressure of hydrogen may be maintained at pressures between about 1.0 Bar to about 19.0 Bar, or about 1.5 Bar to about 12.0 Bar, or about 2.5 Bar to about 10.0 Bar or about 3.0 Bar to about 7.0 Bar

The temperature of the reaction mixture and/or process is maintained in the range of about 20° C. to about 130° C., more preferably in the range of about 40° C. to about 110° C. and most preferred in the 60° C. to 90° C.

Preferably, the alkoxide is potassium or sodium alkoxide. In addition, another embodiment is when the alkoxide is derived from t-butylalcohol [(CH₃)₃COH], t-pentylalcohol [C₂H₅(CH₃)₂COH] or 3-methyl-t-pentylalcohol [CH₃(C₂H₅)₂COH].

In further embodiments, the vinyl aromatic monomer is a styrenic monomer. The organolithium compound is n-butyllithium, sec-butyllithium, tert-butyllithium, iso-butyllithium, phenyllithium, 1-hexyl-1-phenyllithium, cyclohexyllithium or poly(styryl)lithium. The polytertiaryamine is N,N,N′,N′-tetramethylethylenediamine (TMEDA). Also, The aromatic hydrocarbon may preferably be benzene, toluene, mesitylene, o-xylene, m-xylene, ethylbenzene, n-propylbenzene, n-butylbenzene, isobutylbenzene, amylbenzene, 1,3-diarylpropanes or a styrene dimer.

In the above process, the molar ratio of the alkoxide to organolithium compound charged in the reactor is in the range of about 0.25:1.0 to about 10:1; the molar ratio of styrene to organolithium compound is about 10:1 to about 1000:1, and the molar ratio of the tertiary amine to organolithium compound is in the range of about 1.5:1 to about 20:1 and the hourly feed rate of monomer to organolithium is in the range of 10 to 200 moles of monomer per hour per mole of organolithium.

More preferably in the above process, the vinyl aromatic monomer is styrene, the organolithium compound is a butyllithium, the polytertiaryamine is N,N,N′,N′-tetramethylethylenediamine (TMEDA) and the hydrocarbon is ethylbenzene.

The soluble catalyst compositions are formed from (a) an organolithium compound; (b) a polytertiaryamine promoter compound; (c) a metal alkoxide, wherein said alkoxide is an alkali metal alkoxide, or a magnesium alkoxide; (d) optionally an aromatic hydrocarbon having at least one C—H covalent bond pK_(a) within the range of 2.75 pK_(a) units above that of the pK_(a) of toluene to −4.30 pK_(a) units below the pK_(a) of toluene; and (e) a hydrocarbon solvent having a pK_(a) greater than H₂, wherein the aromatic hydrocarbon and hydrocarbon solvent may be the same or different. The product distribution formed from such a process when the monomer is solely styrene hereinafter designated SASH PS distribution.

In the above catalytic composition, the alkoxide is preferably a potassium and/or sodium alkoxide. Also preferable is when the alkoxide is derived from t-butylalcohol [(CH₃)₃COH], t-pentylalcohol [C₂H₅(CH₃)₂COH] or 3-methyl-t-pentylalcohol [CH₃(C₂H₅)₂COH].

In another embodiment of the catalytic composition, the organolithium compound is preferably a n-butyllithium, sec-butyllithium, tert-butyllithium, iso-butyllithium, phenyllithium, 1-hexyl-1-phenyllithium, cyclohexyllithium or poly(styryllithium). I

In yet another embodiment of the catalystic composition, the tertiary amine is preferably N,N,N′,N′-tetramethylethylenediamine (TMEDA).

In the above catalytic composition, the aromatic hydrocarbon is preferably benzene, toluene, o-xylene, m-xylene, mesitylene, ethylbenzene, n-propylbenzene, n-butylbenzene, isobutylbenzene, amylbenzene, 1,3-diarylpropanes or styrene dimer.

Furthermore, in the above catalystic composition, the molar ratio of the alkoxide to organolithium compound is in the range of about 0.25:1 to 10:1; the molar ratio of the polytertiaryamine to organolithium compound is in the range of about 1.5:1 to about 20:1.0 and wherein the partial pressure of hydrogen is maintained at pressures between about 1.0 Bar to about 19 Bar.

In the practice of the invention a precursor to the SASH catalyst can be optionally formed and converted to the SASH catalyst in a variety of methods which are not limited by but include:

-   -   I. forming a well-mixed solution of at least (a) and (b) in (e)         under an inert atmosphere and then converted to SASH by: 1)         feeding a portion of the monomer; 2) feeding (c) dissolved         with (b) in (e) if not already introduced to the reactor; and 3)         replacing or otherwise displacing the inert atmosphere with H₂;         or     -   II. forming a well-mixed solution or suspension of (a), (b),         (c), and (d) in (e) under an inert atmosphere to form a         precursor which is then converted to SASH by replacing or         otherwise displacing the inert atmosphere with hydrogen; or     -   III. forming a well-mixed solution of (b) and (c) in (e) under a         hydrogen atmosphere; feeding a portion of the monomer then         feeding (a) all at once; or     -   IV. forming a well-mixed solution of (b), (c) and (d) in (e)         under a hydrogen atmosphere then feeding (a) over a period         greater than about 3 minutes.

Of these four modes of forming the SASH catalyst (i.e. methods I-IV above), method IV most consistently provides run to run reproducibility. The practice of method IV nearly eliminates the formation of suspended solids, as well as solids that adhere to hot surfaces (i.e. heated reactor walls) and solids that adhere to cold surfaces (i.e. cooling coils, baffles, dip-legs and agitator blades and shafts). Methods I and II are least desired in that these methods enhance the formation of solids and require purging or displacing the inert atmosphere. Method III can be used if no added chain transfer agent is desired for forming the product distribution. The drawback of method III is in order to avoid forming a high molecular weight impurity distribution; (a) must be added rapidly which produces a significant heat release that might be deemed undesirable in a commercial scale reactor. It should be understood that other modes or sequences of combining (a), (b), (c), (d) and (e) in the presence or prior to the introduction of molecular hydrogen along the addition of other reagents or solvents (such as quantities of THF as a Lewis base) can be practiced and are well within the scope of this invention.

It should be understood that in the practice of method IV for forming the SASH catalyst in order to conduct the SASH catalyst process, the molar ratios of the metal alkoxide: organolithium compound and polytertiaryamine:organolithium coumpounds mathematically varies over the range from the limit of ∞:1 from the first drop of the organolithium introduced to the final stoichiometric ratio based on the intended total charge of the active organolithium reagent. Thus it matters not or at least very little what the molar excess of either the metal alkoxide and/or the polytertiaryamine charge is while forming the SASH catalyst used in the practice of the processes of this invention—the catalyst forms with large molar excesses of these reagents. Thus the use of amounts of (a), (b) and (c) outside the preferred ranges of relative ratios of the total charges recited below, such use of such amounts is well within the scope of the present invention. Practice of this invention using catalyst component charge ratios outside the recited preferred ranges of such ratios may at best simply results in inefficient use of raw materials and may at worse provide compositions that interfere with the efficiency in which the SASH catalyst is produced and solubilized.

Non-limiting preferred examples of organolithium compounds suitable for forming SASH catalysts are n-butyllithium, sec-butyllithium, tert-butyllithium, iso-butyllithium, allyllithium, vinyllithium, phenyllithium, 1-hexyl-1-phenyllithium, 1-hexyl-1,1-diphenyllithium, cyclohexyllithium, and poly(styryl)lithium compounds which can be added or generated in situ.

Non-limiting examples of metal alkoxides used in forming a soluble SASH catalyst are those derived from t-butylalcohol [(CH₃)₃COH], t-pentylalcohol [C₂H₅(CH₃)₂COH] and 3-methyl-t-pentylalcohol [CH₃(C₂H₅)₂COH], such as potassium t-butoxide or sodium pentoxide. The alkoxides derived from potassium are preferred.

Non-limiting examples of poly(tertiary amine) promoters useful in SASH catalyst, applications include di(tertiary amine) ligands derived from propylene diamine, di(tertiary amine) ligands derived from ethylene diamine or from polyethylene imine. Preferred examples include N,N,N′,N′-tetramethylethylenediamine (TMEDA), N,N,N′,N″-pentamethyldiethylenetriamine (PMDETA), sparteine, isosparteine, and 1,4-methylpiperazine wherein TMEDA is most preferred. The most preferred poly(tertiary amine) promoter ligands are the most volatile and/or the most water and/or acid soluble compounds thus TMEDA is preferred.

The preferred aromatic hydrocarbon which may be used is any aromatic hydrocarbon having a pK_(a) relative to toluene±2.75 pK_(a) units however it is conceivable that an aromatic hydrocarbon such as diphenylmethane with a pK_(a) of 4.32 units less than toluene can be employed so long as: 1) the incorporation of diphenylmethane moiety in the polymer microstructure does not affect the ultimate end use; and/or 2) the pK_(a) of such hydrocarbons are suffiently above that of H₂ under the reaction conditions so as to not interfere with the hydrogen mediated chain transfer mechanism. Non-limiting examples of aromatic hydrocarbons that may be used are benzene, toluene, mesitylene, ethylbenzene, n-propylbenzene, n-butylbenzene, isobutylbenzene, amylbenzene, 1,2-darylethanes, 1,3-diarylpropanes, cumene, t-butylbenzene, a 1-alkyl naphthalene, 2-alylnaphthalene or a styrene dimer or low molecular weight oligomer distribution (styrene dimers, trimers, tetramers, pentamers, and hexamers). Though the use of such aromatic hydrocarbons is optional, their use is preferred in that it is believed their presence diminishes or preempts or otherwise mitigates the undesired attack of the organolithium more specifically an alkyllithium reagent on the polytertiaryamine promoter. Hydrocarbons that are easily removed from the product distribution by distillation or by polymer precipitation are preferred. The most preferred aromatic hydrocarbon for HMSHIP process utilizing styrene is ethylbenzene.

The hydrocarbon solvent which may be used in any hydrocarbon having a pK_(a) greater than molecular hydrogen (H₂) under the reaction conditions. Non-limiting examples of such preferred solvents are cyclohexane, methyl cyclohexane, and the aromatic hydrocarbons listed above. Other hydrocarbon solvents can be used as long as their use does not affect the solubility of the saline hydride catalyst, reactive intermediates, transient living polymer chains and the polymer chain distribution product.

The aromatic hydrocarbon and the aromatic solvent may be the same or different. This means that the aromatic hydrocarbon can act as both the aromatic hydrocarbon and the solvent. For example, ethylbenzene is a preferred component in the polymerization of styrene and can be used as both the aromatic hydrocarbon and the solvent. In this case, for a SASH process components (d) and (e) would merge into one component (or limitation) and be the same. Likewise, they can be different. For example, the aromatic hydrocarbon may be ethylbenzene and the hydrocarbon may be cyclohexane. Thus components (d) and (e) would be different. Furthermore, component (d) may be optional if no aromatic hydrocarbon is used and, for example, cyclohexane is used as component (e).

The partial pressure of hydrogen in the above SASH catalyst processes is maintained at pressures between about 0.001 Bar to about 10.0 Bar, or about 0.3 Bar to about 6.8 Bar, or about 0.5 Bar to about 5.2 Bar or about 1.0 Bar to about 4.2 Bar. A hydrogen partial pressure greater than about 10.0 Bar is permissible for a period of time during the process when process conditions entail routine operation with adequate mixing to maintain hydrogen transfer to the condensed phase. However a substantial amount of time at such increased hydrogen partial pressures will generally result in hydrogenation of the monomer with a substantial reduction of polymer molecular weight and yield as is predicted by Equation IV that expresses kinetic chain length (v) in terms of hydrogen activity [H₂]. Conversely, hydrogen pressures below 0.1 Bar (less than 1.5 PSI) are permissible during routine operation of the processes involving potassium hydride forms of SASH catalyst. Under such conditions of low hydrogen partial pressure and hence low H₂ activity in the condensed phase, chain transfer from the organic chain transfer agents whether added or formed during the course of the run will compete more substantially. It is pointed out that the partial pressures recited above are only meaningful if adequate mass transfer of molecular hydrogen to the condensed phase is maintained such that the partial pressure reflects the condensed phase activity of molecular hydrogen—i.e. an effective and steady state mass transfer of H₂ to the condensed phase is established. Thus much higher H₂ partial pressures can be applied when mass transfer to the condensed phase is diminished due to poor mixing of the vapor phase with the condensed phase and thus results in poor mass transfer.

In that nitrogen may (though no evidence of this has been observed) potentially be “fixed” by—that is N₂ may be reduced by—the saline hydride catalyst of this invention and because as the reactor headspace volume is reduced by the monomer feed when operating under semi-batch conditions, it is potentially desirable but perhaps not necessary to eliminate or at least minimize N₂ from the reactor headspace and system. It is possible to operate with other gases present which are generally deemed inert toward activated hydrides such as a noble gas (He, Ne, Ar) or a relatively light aliphatic or cycloaliphatic hydrocarbon (hydrocarbon with boiling point close to or less than the reaction temperature). Of these inert gases the relatively light hydrocarbons are preferred because such hydrocarbons are generally soluble in the reaction medium and hence do not displace H₂ and thereby reduce the partial pressure of H₂ in significantly varying amounts during the course of the monomer feed at a constant reactor pressure. Thus inert gases that become compressed in the head space as the condensed phase volume increases are less desired. However the presence of such low solubility gases such as the noble gases in a continuous process where the headspace volume is fixed may perhaps be used to some benefit. It is difficult to operate a commercial reactor at low positive pressures of constant pressure thus it may be advantageous to have present low boiling (petroleum ethers) hydrocarbons such that a desired H₂ partial pressure and hence activity can be maintained at a higher overall reactor pressure. Such light hydrocarbons can even provide the added benefit of some means of refluxive cooling.

For the SASH process, the molar ratio amount of the metal alkoxide:organolithium (active) compound is 1:3 to about 3:1, or about 0.66:1 to about 1.33:1, or about 0.7:1 to about 1:1. The practitioner can use a ratio of metal alkoxide:organolithium (active) outside of the preferred range so long as the added excess reagents do not interfere with forming the soluble SASH catalyst. A slight molar excess (e.g. up to about 30% excess) of the initially charged organolithium compound appears to improve the resulting SASH catalyst solubility in aromatic hydrocarbons. The use of metal alkoxide:organolithium much above or below ratio of [1:1] generally requires an increase in the charge of the polytertiaryamine. Significantly higher ratios where the organolithium is in a large excess runs the risk of forming the less soluble lithium form of the SASH catalyst (i.e. nanometric lithium hydride particles of very low solubility and activity in the SASH catalyst process see Examples 42 and 43 below). Though permissible conditions that lead to formation of such nanometric lithium hydride solids could constitute an uneconomic use of the expensive reagent.

The molar ratio of the total charge of monomer to metal hydride compound initially formed, (monomer:metal hydride), is about (10.0:1.0) to about (1000.0:1.0), or about (40.0:1.0) to about (600.0:1.0), or about (150.0:1.0) to about (360.0:1.0). Whereas the molar quantity of metal hydride formed is taken as being equal to the molar quantity of organolithium carbon-metal bonds, the conjugate acid thereof having a pK_(a)>H₂— that remain after reaction with all protic species having a pK_(a)<H₂ under the conditions of the catalyst forming reactions. Any decrease in the amount of metal hydride due to decomposition reactions is not taken into account and conditions (e.g. temperatures) as well as reagents (e.g. organic species such as certain ethers that easily undergo metalation and decomposition by organolithium reagents) that contribute to catalyst deactivation are simply best avoided.

In the batch or semi-batch operation of the process technology of this invention the monomer (e.g. styrene) is fed with time to the reaction medium, hence the initial ratio monomer:organolithium at the very moment that the vapor from the first drop or increment of monomer fed is introduced to the reactor is mathematically approaching the limit (1:∞). Thus a total monomer charged to organolithium compound charged molar ratio outside the preferred recited ranges—i.e. a molar ratio in the range of from the limit of (1.0:∞ to about 1.00:0.101 which is about 9.9:1.0) monomer to organolithium—are demonstrated as workable ranges at the outset of each of the Examples provided below. However the monomer feed is generally continued until the higher desired monomer to metal hydride ratio is complete. The practice of a charge molar ratio limited to from the limit of (1.0:∞ to 1.00:0.10) is within the scope of the invention but simply represent uneconomical utilization of the organolithium compound.

Conversely feeding monomer at a relative molar ratio to organolithium greater than about 1000:1 becomes unworkable; resulting in diminished chain transfer producing compositions of undesired molecular weight distributions (MWD). The theoretical M_(n) (M_(n Th) a.k.a. M_(calc)) for a SASH polystyrene distribution formed from a ratio of 300:1 of styrene:organolithium compound is M_(n Th) 300*104=31,200 Daltons. A typical hydrogen mediated SASH catalyst anionic chain transfer process employing 300:1 monomer to catalyst charge ratio can provide a pure polystyrene composition having M_(w)=1000. Thus the Eff_(CT)=31,200/600=52 and the amount of organolithium reagent needed to form a 600 M_(n) composition is reduce 5200%. Charges well above about 600:1 are within the scope of the invention for the SASH processes but are less desired.

For the SASH process the molar ratio amount of the polytertiaryamine (PTA) promoter, when employing a monomeric PTA composition, relative to the total metal—i.e. the molar quantity of combined alkali and alkaline earth metal present in any form—charged, (PTA:metal) is about (1.2:1) to about (8:1), or about (1.3:1) to about (4:1) or about (1.8:1) to about (2.7:1). The amount of polytertiaryamine should be the amount needed to sufficiently dissolve the alkali metal alkoxide in the initially formed reaction medium and an amount needed to solubilize the SASH catalyst and promote the hydrogen chain transfer mechanism. Catalyst activity and apparently solubility of the SASH catalyst may both increase with increased molar ratios of (PTA:metal). But such increases in activity should level off and so charge ratios much above (4:1) offer little advantage if any and may lead to increased impurities formed from the excess free (not complexed to catalyst) polytertiaryamine.

The monomer feed rates relative to the amount of catalyst is among the determining kinetic factors with regard to setting the polymer composition's polydispersity, PD_(n), and hence the overall molecular weight distribution (MWD) as measured by the values of M_(n), M_(w), M_(z), PD_(n), number average standard deviation (σ_(n)), and asymmetry (_(n)α₃). It is therefore advisable to feed the monomer in certain relative rates at given H₂ activity (or partial pressure) in a given reactor design or geometry. It should be clear that a very small relative feed rate (i.e. less than about 15 moles monomer/hr/moles active Li) of the monomer to the catalyst will produce an undesired level of reduced (essentially hydrogenated) monomer and with some dimer. Furthermore the compositions produced have high asymmetry values and are less desired. On the other hand very high relative feed rates generally form higher molecular weight distributions, such compositions that can otherwise be economically produced with little to no chain transfer. Because neither the empirical nor molecular formula of the SASH catalyst is determined or necessarily defined, nor is the molecular weight of the these catalysts known, the hourly feed rate of monomer (styrene) relative to catalyst is expressed in terms of the amount of active hydride presumed to be present in the catalyst. It is assumed that each equivalent mole of active organolithium forms one equivalent mole of a saline hydride. Thus in the practice of this invention, the hourly feed rate of monomer to saline hydride compound should be in the range of from about 10 to about 350 moles of monomer per hour per mole of active saline hydride reagent charged in the reactor, or more preferably in the range of from about 65 to about 260 moles of monomer per hour per mole of saline hydride initially formed in the reactor. Again the equivalent mole of saline hydride is taken as being equal to the molar equivalent of the active organolithium initially charged when the catalyst is formed. Again active organolithium means the amount of organolithium groups left after reaction with any and all protic species having a pK_(a) less than H₂ present in the reaction mixture. These remaining active organolithium groups are then taken as being completely converted to the active saline hydride by molecular hydrogen though the process can entail the intermediary formation of another saline metal group. For example n-butyllithium is likely converted to a transitory n-butylpotassium reagent before reduction to form a super active potassium hydride catalyst but the amount of potassium hydride is related to the amount of active n-butyllithium.

The temperature of the reaction mixture during the course of the monomer feed is maintained in the range of about 20° C. to about 130° C., or in the range of about 40° C. to about 99° C., or in the range of about 60° C. to about 90° C. It is conceivable that higher temperatures can be employed during the entire run or during a portion of the run; however temperatures that accelerate any decomposition of the catalyst and/or cause the elimination of hydride from the polymer chains and formation of chain lengths terminated with unsaturated bonds are best avoided. The amount of such hydride elimination termination reactions should vary with temperature and catalyst composition. In forming the SASH catalyst and during the initial heat up, the catalyst can be combined at the temperature just above the melting temperature of the hydrocarbon solvent (or mixture of solvents) or the freezing point of the monomer that is being fed. Combining the catalyst components at low temperatures (i.e. −10 to 15° C.) and even under cryogenic conditions (−10° C. to −126° C.) may have the benefit of avoiding or suppressing lithiation or other metalation reactions that can lead to partial decomposition of the poly(tertiaryamine) promoter. However conditions that result in precipitation of the saline hydride catalyst or its precursor transitory complexes and reagents are perhaps best avoided.

The desired level of dispersal of monomer in the reaction medium will depend upon the efficiency by which hydrogen is transported from the vapor phase and/or hydrogen gas feed to the condensed phase throughout the course of a run. Ideally a commercial scale, pilot scale and even bench scale reactor can be designed and configured such that hydrogen transfer from the vapor phase to the condensed phase is essentially uniform throughout the course of the monomer feed. Under such uniform hydrogen transport between phases, it is desirable to minimize the reduction of monomer to its saturated analog by feeding the monomer such that a locally high concentration exists in the reactor. In bench or small pilot scale reactors such locally high monomer concentrations is accomplished by employing very high relative monomer to catalyst feed rates and ratios with the use of relatively low feed velocities. In large commercial equipment monomer is fed to a reaction zone which can be physically apart or separated from the bulk of the reaction mixture (i.e. a pump-around-loop).

Upon completion of the SASH catalyst process monomer feed and reaction, as indicated, for example, by rapid reduction in the process temperature at constant heat flux and/or the termination of uptake of H₂, the reaction mixture is maintained under hydrogen pressure and then transferred to a wash reactor for quenching and water washing. The wash reactor charged with water (with or without acid and a mineral acid such as H₂SO₄ or an organic acid such as acetic acid). Additionally the wash reactor can be previously charged with an optional additional amount of a hydrocarbon solvent. The quench can be conducted with cooling or at ambient temperatures up to the temperature at which the hydrocarbon solvent forms an azeotrope with water under the pressure conditions of the wash reactor. The product is water washed to remove alkali metal salts and at least a portion of the promoter and polarizing agent. Under very acidic conditions such reagents are nearly completely removed with the alkali and alkaline earth metal salts formed from the acid. Under basic conditions where an equivalent of acid or less is used the promoter is partitioned between the organic reaction mixture and the aqueous wash. Water washing is continued until the desired pH of the exiting wash water is obtained. Under basic conditions a pH of 9 to a pH of 11 indicates that all the alkali and alkali earth metal salts have been removed. Under acidic conditions a pH of 6 to a pH of 8 (depending on the alkalinity of the wash water) indicates that all acidic species have been removed or at least neutralized.

When the wash is deemed complete solvent and a portion of any remaining polytertiaryamine promoter and monomer reduction product are preferably separated and recovered from the reaction mixture, whereby the last traces of water are also removed azeotropically from the reaction mixture. This separation operation should be continued until monomer reduction product content of the resultant product mixture is less than about 0.1 wt %. Further modification and shaping of the product distribution by reducing the monomer dimer content is desirable for some applications. For high boiling dimers this is easily conducted using a wiped film evaporator.

The most preferred initially formed hydrogen mediated saline hydride initiated styrenic distributions are formed exclusively from styrene monomer and hydrogen and have a chain length distribution of the above structure. Said chain length distribution is comprised of i−1 discrete polymer chain lengths in a statistical number average distribution of the relative molar content where i is a positive integer from i=2 to i=i. Thus for (Chain-1) when n=0 (styrene dimer) then i=2; (Chain-2) when n=1 (styrene trimer) then i=3; (Chain-3) n=2 (styrene tetramer) then i=4; (Chain-4) when n=3 (styrene pentamer) then i=5; (Chain-5) when n=4 (styrene hexamer) then i=6; . . . and (Chain−(i−1)) when n=i−2 then i=i. Thus the (i−1)^(th) discrete polymer chain is the discrete polymer chain of the greatest chain length. We have found that in general the GPC molecular weight distribution (MWD) analysis results for the polymer compositions of this invention can be reasonably modeled with a gamma probability density function (PDF). More importantly however we have found that compositions formed from a SASH catalyst generally more accurately modeled with a Beta PDF; which would indicate that for the SASH catalyzed process the molecular weight distribution is set by chain transfer along with significant regeneration of dead polymer chains (styrene dimer) as well as indicates activation, participation or incorporation of ethylbenzene as an organic chain transfer agent in forming the polymer distribution.

The molecular weight distributions of the chain length distributions of this invention when styrene is the monomer are characterized where M_(n) is in the range of from 315 to 905 Daltons; Mw is in the range of from about 392 to about 1716 Daltons; and M_(z) is in the range of about 512 to 3031 Daltons; PD_(n) is in the range of 1.24 to 1.90; with a standard deviation in the range of 156 to 857 Daltons and the asymmetry is in the range of 1.40 to about 3.14. More preferred compositions have molecular weight distributions where M_(n) is in the range of from 410 to 680 Daltons; Mw is in the range of from about 553 to about 1205 Daltons; and M_(z) is in the range of about 745 to 1950 Daltons; PD_(n) is in the range of 1.29 to 1.82; with a standard deviation in the range of 257 to 600 Daltons and the asymmetry is in the range of 1.50 to about 2.60. Most preferred compositions have molecular weight distributions where M_(n) is in the range of from 444 to 683 Daltons; Mw is in the range of from about 600 to about 1150 Daltons; and M_(z) is in the range of about 798 to 1768 Daltons; PD_(n) is in the range of 1.35 to 1.68; with a standard deviation in the range of 263 to 565 Daltons and the asymmetry is in the range of 1.50 to about 2.31.

Preferred non-blended compositions of this invention are comprised essentially only if not solely of styrene and have had their chain length distribution further shaped or modified by removal of a portion of the lowest molecular weight chains. Removal of the lower molecular weight chains, especially styrene dimer—like removing the lowest value(s) or a portion of the lowest value(s) from all other arithmetic averages (e.g. a grade point average)—results in a new average with an increased overall molecular weight distribution. Thus the preferred modified molecular weight distributions of this invention will overlap with the unaltered distributions but may not lie within the range of molecular weight distributions or molecular weight parameters specified above because of the simple numerical consequence of having been altered. Thus preferred compositions where the dimer has been reduced but is still present and represents 0.1 to 1.0 wt % (as determined by GPC analysis) of the entire distribution have molecular weight or chain length distributions where M_(n) is in the range of from 407 to 968 Daltons; Mw is in the range of from about 487 to about 1746 Daltons; and M_(z) is in the range of about 579 to 3038 Daltons; PD_(n) is in the range of 1.40 to 1.80; with a standard deviation in the range of 180 to 868 Daltons and the asymmetry is in the range of 1.31 to about 3.12. More preferred compositions have molecular weight distributions where M_(n) is in the range of from 494 to 788 Daltons; Mw is in the range of from about 623 to about 1278 Daltons; and M_(z) is in the range of about 782 to 1964 Daltons; PD_(n) is in the range of 1.26 to 1.62; with a standard deviation in the range of 253 to 621 Daltons and the asymmetry is in the range of 1.40 to about 2.40. Most preferred compositions have molecular weight distributions where M_(n) is in the range of from 521 to 737 Daltons; Mw is in the range of from about 661 to about 1202 Daltons; and M_(z) is in the range of about 827 to 1783 Daltons; PD_(n) is in the range of 1.27 to 1.63; with a standard deviation in the range of 270 to 586 Daltons and the asymmetry is in the range of 1.40 to about 2.50.

It is pointed out that blending operations where statistical distributions are combined can result in non-statistical distributions where the provided constraints of for Par, standard deviations would not be applicable. However such blends are within the scope of this invention in that they are formed by combination of compositions of and formed from this invention.

Another embodiment of the present application is a hydrocarbon soluble catalyst or reagent composition formed from: (a) molecular hydrogen; (b) an organolithium compound; (c) a polytertiaryamine compound; (d) an alkoxide, wherein said alkoxide is an alkali metal alkoxide, and/or a magnesium alkoxide and/or calcium; (e) optionally an aromatic hydrocarbon having at least one C—H covalent bond pK_(a) within the range of 2.75 pK_(a) units above that of the pK_(a) of toluene to −4.30 pK_(a) units below the pK_(a) of toluene; and in (f) a hydrocarbon solvent; wherein the aromatic hydrocarbon and hydrocarbon solvent may be the same or different; wherein the solubility of hydride comprising said catalyst is at least about 0.010 moles per liter and more preferably greater than about 0.10 moles per liter; and wherein when the metal alkoxide is a magnesium alkoxide the optional aromatic hydrocarbon is a vinyl aromatic monomer.

The same non-limiting examples and amounts of the components listed above for the SASH catalyst process may be used in the above catalytic composition and need not be repeated.

Components referred to by chemical name or formula anywhere in the specification or claims hereof, whether referred to in the singular or plural, are identified as they exist prior to coming into contact with another substance referred to by chemical name or chemical type (e.g., another component, a solvent, or etc.). It matters not what chemical changes, transformations and/or reactions, if any, take place in the resulting mixture or solution as such changes, transformations, and/or reactions are the natural result of bringing the specified components together under the conditions called for pursuant to this disclosure. Thus the components are identified as ingredients to be brought together in connection with performing a desired operation or in forming a desired composition. Also, even though the claims hereinafter may refer to substances, components and/or ingredients in the present tense (“comprises”, “is”, etc.), the reference is to the substance, component or ingredient as it existed at the time just before it was first contacted, blended or mixed with one or more other substances, components and/or ingredients in accordance with the present disclosure. The fact that a substance, component or ingredient may have lost its original identity through a chemical reaction or transformation during the course of contacting, blending or mixing operations, if conducted in accordance with this disclosure and with ordinary skill of a chemist, is thus of no practical concern.

The invention described and claimed herein is not to be limited in scope by the specific examples and embodiments herein disclosed, since these examples and embodiments are intended as illustrations of several aspects of the invention. Any equivalent embodiments are intended to be within the scope of this invention. Indeed, various modifications of the invention in addition to those shown and described herein will become apparent to those skilled in the art from the foregoing description. Such modifications are also intended to fall within the scope of the appended claims.

The following Examples illustrate the present invention. It is to be understood, however, that the invention, as fully described herein and as recited in the Claims, is not intended to be limited by the details of the following Examples

HASH Catalyst Process Examples 1-3

Examples 1-3 provide non limiting examples of the HASH catalyst process. The apparatus used for the HASH catalyst process has been previously described in U.S. Pat. Nos. 5,771,169 and 5,866,720.

Example 1 HASH Catalyst Styrene Polymerization with Biphenyl Entraining Agent

Anhydrous tetrahydrofuran 820 g, 5 ml (4.33 g, 0.128 g-atoms alkali metal) of sodium potassium alloy (NaK₂) and 0.50 g (0.00324 mole) biphenyl were charged to the reactor at 20° C. under a dry nitrogen atmosphere. The unstirred reaction mixture was purged of nitrogen with hydrogen (3×65 PSIG) and the pressurized to 50 PSIG H₂. High speed high sheer mixing (1900 RPM) applied and styrene, 200.0 g (1.92 mole), was fed over 70 minutes (3.15 ml/min) to the reaction mixture. During the styrene monomer feed the reactor pressure was maintained between 50 and 40 PSIG H₂. Upon completion of the feed the reactor was vented of H₂ and the reaction mixture was carefully quenched with isopropyl alcohol. A sample of the quenched reaction mixture was analyzed by GPC and had the following MWD: M_(n): 965, M_(w): 2005, M_(z): 3318, PD: 2.078, σ_(n)=1002, _(n)α₃=2.602.

Example 2 HASH Catalyst Styrene Polymerization

Anhydrous tetrahydrofuran 820 g and 4.8 g (0.142 g-atoms alkali metal) of sodium potassium alloy (NaK₂) were charged to the reactor at 20° C. under a dry nitrogen atmosphere. The unstirred reaction mixture was purged of nitrogen with hydrogen (3×65 PSIG) and the pressurized to 55 PSIG H₂. High speed high sheer mixing (1900 RPM) applied and styrene, 217.0 g (1.92 mole), was fed over 76 minutes (3.15 ml/min) to the reaction mixture. During the styrene monomer feed the reactor pressure was maintained between 55 and 45 PSIG H₂. Upon completion of the feed the reactor was vented of H₂ and the reaction mixture was carefully quenched with isopropyl alcohol. A sample of the quenched reaction mixture was analyzed by GPC and had the following MWD: M_(n): 897, M_(w): 1677, M_(z): 2722, PD: 1.87, σ_(n)=836, _(n)α3=2.55.

Example 3 HASH Catalyst Styrene Polymerization w/o Entraining Agent

Anhydrous tetrahydrofuran 818 g and 6.2 g (0.183 g-atoms alkali metal) of sodium potassium alloy (NaK₂) were charged to the reactor at 20° C. under a dry nitrogen atmosphere. The unstirred reaction mixture was purged of nitrogen with hydrogen (3×70 PSIG) and the pressurized to 70 PSIG H₂. High speed high sheer mixing (1900 RPM) applied and styrene, 208.0 g (2.00 mole), was fed over 73 minutes (3.15 ml/min) to the reaction mixture. During the styrene monomer feed the reactor pressure was maintained between 70 and 60 PSIG H₂. Upon completion of the feed the reactor was vented of H₂ and the reaction mixture was carefully quenched with isopropyl alcohol. A sample of the quenched reaction mixture was analyzed by GPC and had the following MWD: 591, M_(w): 943, M_(z): 1438, PD: 1.60, σ_(n)=456, _(n)α3=2.38. The reaction mass is transferred to a creased wash reactor containing ethylbenzene stripped of THF and then water washed. Further stripping on a wiped film evaporator WFE (2″ glass Pope Still, graphite blades, operated at 300.0 mmHg vacuum, 140° C., 60% of full wiper speed feeding at 1.0 liter/hr rate) produced 191 g of a polystyrene resin having GPC MWD: M_(n): 603, M_(w): 956, M_(z): 1373, PD: 1.58, σ_(n)=461, _(n)α₃=1.906. A 164 g sample of the 191 g from above was subjected to a second WFE operation (at 0.4 mmHg vacuum, 230° C., 60% of full wiper speed feeding at 1.0 liter/hr rate) yielding 153.6 g of a resin having GPC MWD: M_(n): 802, M_(w): 1081, M_(z): 1418, PD: 1.35, σ_(n)=473, _(n)α₃=1.645.

SASH Catalyst Process Examples 4-60

Examples 4 through 60 provide processes for SASH catalyst process forming distributions of polystyrene polymer compositions of this invention.

General Apparatus Used

The apparatus used for HMSHIP processes is as follows. A 316 stainless steel 2-liter Parr autoclave having thermal couple, bottom drain valve, cooling coils, hot oil jacket and either two or three pitch-blade turbine impellers (with placement of each impeller as noted in the Examples) was further equipped with a piston pump, a diaphragm pump, nitrogen purged 250 ml stainless charge vessel, a well calibrated high pressure metering pump and a 1/16th inch OD subsurface monomer feed line having either a 0.02″, or a 0.01″ or a 0.007″ ID terminal section (as noted in the Examples). The magnetic drive on the agitator is connected to a high speed air driven motor and generally operated such that the stirrer impellers spin at a rate of 1130±25 RPMs. The autoclave is vented to an oil bubbler and/or to a 6-liter oil jacketed creased wash vessel having a bottom drain and outfitted for overhead stirring and distillation. The bottom drain valve and the dip-leg sampling port are both plumbed to the wash vessel for direct transfer of the unquenched reaction mixture. Bulk solvent (e.g., cyclohexane or ethylbenzene or a mixture thereof recovered from a previous run) is charged to the reactor via piston pump through the charge vessel. The catalyst components (e.g., TMEDA/potassium t-butoxide/solvent solution and butyllithium) are charged separately to the reactor through the charging vessels. The contents of the charge vessel are pressure transferred with a minimum of nitrogen to the autoclave having either nitrogen or a hydrogen or a hydrogen/nitrogen atmosphere. Styrene is fed via high pressure metering pump through basic alumina columns to remove the inhibitor at predetermined constant rate. Hydrogen is fed to the head space and/or subsurface and maintained at the desired pressure. The autoclave reactor is heated with oil having a temperature set point at or just above (+1° C. to +3° C.) the desired reaction temperature and the reaction temperature was tightly maintained at the predetermined set point once the reactor controller lined out (generally after the first 20-30 minutes of the monomer feed when starting at ambient temperature). Thus the reaction temperature might have brief excursion in temperature generally no more than 5° C. above the desired set-point temperature.

During the course of the development of this invention 3 separate configurations (Configurations I-III below) or placements involving two, three or four pitch-blade turbine impellers was utilized:

-   -   I. Two pitch blades with the first 6.25″ and the second 10″ from         the top of the reactor.     -   II. Two pitch blades with the first 5.5″ and the second 10″ from         the top of the reactor.     -   III. Three pitch blades with the first 4.0″, the second 6.75″         and the third 10″ from the top of the reactor.

Thus Configuration I generally resulted in a significant reduction in hydrogen up take during the last one third of the monomer styrene feed. Configurations II and III generally resulted in an intermediate slowing of the uptake of hydrogen during the course of the feed with the hydrogen uptake restored during the latter half of the feed. In that the polymerization reactor is 2000 ml in volume having a maximum working volume of 1750 ml and the initially formed reaction mixture is typically 400 to 600 ml in volume, then the maximum volume of styrene that can be safely fed is in the range of 1350 ml to 1150 ml (not accounting for temperature or changes in density upon polymerization). Thus feeding such volumes of styrene (1150 ml to 1350 ml) is deemed as a full charge of styrene or of monomer for this reactor configuration. The terms full charge of styrene or partial charge of styrene or any term or other phrase used to imply a fractional portions of styrene charged are limitations or restrictions for the apparatus as described above and in no way represents a limitation on the processes or practice of this invention in a reactor system(s) having a different reactor geometry or configuration or mode of operation (batch, semi-batch, semi-continuous, continuous, back-mixed or plugged flow are all modes and/or configurations within the scope of this invention). The Examples recited below are representative of batch or semi-batch operations of this invention. Clearly one of ordinary skill in the art can take the teachings of these Examples and extend the application of this invention to include modes of operation that entail continuous operation with and/or without some level of back mixing and accordingly such modes are well within the scope of this invention.

When charges are made to the polymerization reactor under a nitrogen atmosphere, the autoclave reactor is purged at least 3 times by pressurizing and then venting with 65 PSIG H₂ (65 PSIG to 0 PSIG). The polymerization reactor is then pressurized to the desired H₂ pressure. If reactor charges are made to the reactor containing a hydrogen atmosphere, then the reactor is pressure and vented 2 times with 50 PSIG H₂. Styrene (99%, Acros), TMEDA (Aldrich), Potassium t-Butoxide (97% Alfa Aesar), n-Butyllithium (2M in Cyclohexane, Aldrich), are each used as received from the vendor. Anhydrous cyclohexane, and ethylbenzene (both Aldrich) are handled under an inert dry nitrogen atmosphere. The reaction mixture is quenched by transfer to the wash reactor.

Examples 4-9

The experimental details of Examples 4-9 (reaction conditions, reagent charges, and initial as well as final catalyst concentration), scale-up parameters (relative feeds and relative monomer hourly feed rates) and results (polymer molecular weight distribution as determined by GPC and polymer yield) are presented in tabular form in Table III. Catalyst concentration is expressed as ppm KH*, this calculation assumes that all KH formed is in the super active form and is soluble in the reaction medium as a single saline hydride species (not an aggregate) ignoring any complex formed with TMEDA (in the mass calculation) and any amount of catalyst that exist on a living polymer chain or polymer initiating species. It is expressed this way for descriptive purposes only to simplify the comparison of one embodiment of this invention with yet another. For illustrative purposes Example 4 and Example 6 are described in greater detail below.

Example 4 Demonstrates Preliminary Catalyst Screening Reaction Employing Reduced Styrene Feed Volume

Anhydrous cyclohexane 500 g, was charged to the reactor at 23° C. under a dry nitrogen atmosphere. To the stirred solvent (800 RPM, twin pitch blade impellers, blade placement Configuration I) was charged through the charge vessel a solution previously formed from 11.2 g (0.998 mol.) potassium t-butoxide, 1.06 g (0.01 mol.) ethylbenzene, and 47 g (0.404 mol.) TMEDA. The vessel and line to the reactor was flushed with a 75 g portion of cyclohexane. Next 50 ml (0.100 mol.) 2.0 M n-butyllithium was transferred through the charge vessel to the reactor followed by a 50 g aliquot of cyclohexane. The reactor agitation was increased to 1130 RPM and then purged of N₂ by pressuring to 65 PSIG with dry H₂ (through the headspace) and venting three times (slowly venting to keep the contents from foaming out of the reactor). The H₂ regulator to 25 PSIG and 200 g (1.92 mol.) styrene was fed through a subsurface feed line (0.01″ ID tip, 5.2 ft/s) against the hydrogen head pressure over a period of 46 minutes while maintaining the reactor temperature at 27° C. At the end of the styrene feed, the monomer feed line to the reactor, including the alumina column, were flushed with 50 ml of anhydrous cyclohexane. The styrene feed and flush to the reactor was deemed complete when no further heat of reaction was observed generally signified by the permanent closing of the automated control valve on the coiling coils. During the course of the run the valve to the hydrogen regulator was periodically closed to verify uptake of hydrogen during the styrene feed.

Standard Workup Procedure

The unquenched content of the reaction mixture was transferred to the wash vessel (N₂ atmosphere) previously charged with 300 ml of deoxygenated water heated to 65° C. Thus the reaction mixture is quenched with care in the wash reactor. The reaction mixture was then washed with deoxygenated water (3×300 ml total). Phase cuts were made at 60° C., and were rapid requiring little settling time. Water and any rag or emulsion was removed through the bottom drain valve. The pH of the wash water removed from the reactor was monitored, the first wash invariably had pH=14. Additional deoxygenated water washes (≈300 ml) were conducted until the removed water wash phase had a pH=10 indicating that all alkali metal had been removed. As a note to other experiments, in general a total of 3 washes and never more than 5 washes were needed to reach a pH=10 (standard pH paper). An aliquot of the wash reaction mixture was removed for analysis via GPC (M_(n): 357, M_(w): 545, M_(z): 936, PD: 1.53, σ_(n)=259, _(n)α₃=3.72).

Example 6 Representative of Full Scale Monomer Feed Volume for SASH Catalyst Runs in Cyclohexane at Moderate Temperatures 56°−65° C. Runs

Anhydrous cyclohexane 250 g, was charged to the reactor at 23° C. under a dry nitrogen atmosphere. To the stirred solvent (1130 RPM, twin pitch blade impellers, blade placement Configuration I) was charged through the charge vessel a solution previously formed from 3.27 g (0.0291 mol.) potassium t-butoxide, 3.56 g (0.0336 mol.) ethylbenzene, and 15.00 g (0.129 mol.) TMEDA. The charge vessel and transfer line to the reactor was flushed with a 70 g portion of cyclohexane. Next 14.56 ml (0.0291 mole) 2.0 M n-butyllithium was transferred through the charge vessel to the reactor followed by a 70 g aliquot of cyclohexane. Agitation was increased to 1130 RPM and the reactor purged of N₂ by pressuring to 65 PSIG with dry H₂ (through the headspace) and venting three times (slowly venting to keep the contents from foaming out of the reactor). The H₂ regulator was set to 19 PSIG, the reactor was heated to 60° C. and 911 g (8.75 mol.) styrene was fed through a subsurface feed line (0.01″ ID tip, 5.2 ft/s) against the hydrogen head pressure over a period of 208 minutes maintaining the reactor at 66° C. At the end of the styrene feed, the monomer feed line to the reactor, including the alumina columns, were flushed with 50 ml of anhydrous cyclohexane. The styrene feed and flush to the reactor was deemed complete when no further heat of reaction was observed generally signified by the permanent closing of the automated control valve on the coiling coils. During the course of the run the valve to the hydrogen regulator was periodically closed to verify uptake of hydrogen during the styrene feed. After ca. 90% of the styrene feed had been completed, hydrogen up take had slowed considerably.

The unquenched content of the reaction mixture was washed following the Standard Workup Procedure. An aliquot of the washed reaction mixture was removed for analysis via GPC (M_(n): 455, M_(w): 697, M_(z): 1044, PD: 1.53, σ_(n)=332, _(n)α₃=2.37).

Standard Product Isolation Procedure

The product was stripped in the wash reactor of cyclohexane, TMEDA and ethylbenzene by normal distillation while gradually heating the wash reactor's jacket temperature to 165° C. The distillation was deemed complete when the pot temperature reached a temperature above 135° C. The solution was allowed to cool before collecting 939 g of solution. The solution was then further stripped of ethylbenzene and TMEDA with the use of a wiped film evaporator (WFE, 2″ glass Pope Still, operated at 50.0 mmHg vacuum, 140° C., 60% of full wiper speed, feeding at 1.0 liters/hr). This first WFE operation produced 677 g of a super active saline hydride initiated polystyrene distribution (SASH PS distribution) having GPC MWD of M_(n): 357, Mw: 545, M_(z): 936, PD: 1.53, σ_(n)=259, _(n)α₃=3.72. A second WFE operation. (0.1-0.3 mmHg vacuum, 120° C., 60% of full wiper speed, feeding at 1.0 liters/hr) provided 638.1 g of a SASH PS distribution having 12.26 GPC area % styrene dimer content and a GPC MWD of M_(n): 483, M_(w): 724, M_(z): 1066, PD: 1.50, σ_(n)=341, _(n)α₃=2.30.

Examples 10-19

The experimental details of Examples 10-19 (reaction conditions, reagent charges, and initial as well as final catalyst concentration), scale-up parameters (relative feeds and relative hourly feed rates) and results (polymer molecular weight distribution as determined by GPC and polymer yield) are presented in tabular form in Table IV. Product yields in excess of 100% represent a net incorporation of the organic chain transfer agent, which in these examples is ethylbenzene. Product yields of less than 100% represent a net production of ethylbenzene. SASH Catalyst Example 14 resulted in a 100% yield on the SASH PS polymer distribution for the entire distribution which includes all discrete polymer chains (i.e. all chains dimers and above). Example 14 provided an 88% SASH PS polymer distribution yield after removal of dimer and is considered representative of the practice of the 10 Examples of Table IV. Thus Example 14 is described in greater detail below.

Example 13 Representative of 80% Monomer Feed Volume for SASH Catalyst Runs in Ethylbenzene at Moderate Temperatures 70° C.

Anhydrous ethylbenzene 200 g of 300 g (2.83 mole), was charged to the reactor at 20° C. under a dry nitrogen atmosphere. To the stirred solvent (800 RPM, twin pitch blade impellers, blade placement Configuration I) was charged through the charge vessel a solution previously formed from 4.57 g (0.0407 mol.) potassium t-butoxide, 44 g (0.41 mol.) ethylbenzene, and 20.83 g (0.179 mol.) TMEDA. The charge vessel and transfer line to the reactor was flushed with a 50 g portion of ethylbenzene of the 300 g above. Next 20.34 ml (0.0407 mole) 2.0 M n-butyllithium was transferred through the charge vessel to the reactor followed by a 50 g aliquot of ethylbenzene from above. The reactor was heated to 65° C. Agitation was then increased to 1130 RPM and the reactor purged of N₂ by pressuring to 65 PSIG with dry H₂ (through the headspace) and venting three times (slowly venting to keep the contents from foaming out of the reactor). The H₂ regulator was set to 11 PSIG and 800 g (7.68 mol.) styrene was fed through a subsurface feed line (0.01″ ID tip, 5.2 ft/s) against the hydrogen head pressure over a period of 183 minutes controlling the temperature at 70° C. At the end of the styrene feed, the monomer feed line to the reactor, including the alumina columns, were flushed with 50 ml of anhydrous cyclohexane. The styrene feed and flush to the reactor was deemed complete when no further heat of reaction was observed generally signified by the permanent closing of the automated control valve on the coiling coils.

The unquenched content of the reaction mixture was transferred to the wash reactor and then washed following the Standard Workup Procedure. During the transfer of the unquenched reaction mixture a 10 ml sample of the reaction mixture is obtained for analysis. The sample is red in color and transparent to light giving it an appearance similar to the color of a living APS process sample. The sample's appearance is completely unlike the characteristic dark black-red (black cherry) color of samples anionic chain transfer polymerization conducted in the absence of a hydrogen atmosphere. Such samples of SASH catalyst where the catalyst components are combined under N₂ before forming the hydride generally can contain large (mm size) catalyst particles. The sample is quenched by the addition of a drop of methanol which immediately quenches the red color and results in the immediate formation and evolution of hydrogen gas. GPC Analysis of the crude quenched reaction mixture was as follows: M_(n): 367, M_(w): 497, M_(z): 695, PD: 1.35, σ_(n)=218, _(n)α₃=2.38.

The product was then isolated following the Standard Product Isolation Procedure to yield 827.9 g of a SASH PS distribution having GPC MWD of M_(n): 376, M_(w): 508, M_(z): 707, PD: 1.35, σ_(n)=223, _(n)α₃=3.34. THE second WFE operation (0.1-0.3 mmHg vacuum, 172.5° C., 60% of full wiper speed, feeding at 1.0 liters/hr) provided 608.7 of a SASH PS distribution having 0.99 GPC area % styrene dimer content and a GPC MWD of M_(n): 486, M_(w): 593, M_(z): 750, PD: 1.22, σ_(n)=228, _(n)α₃=2.15.

Example 14 Representative of Full Scale Monomer Feed Volume for SASH Catalyst Runs in Ethylbenzene at Moderate Temperatures 65° to 75° C.

Anhydrous ethylbenzene 200 g of 300 g (2.83 mole), was charged to the reactor at 20° C. under a dry nitrogen atmosphere. To the stirred solvent (800 RPM, twin pitch blade impellers, blade placement Configuration I) was charged through the charge vessel a solution previously formed from 3.02 g (0.0269 mol.) potassium t-butoxide, 43.5 g (0.41 mol.) ethylbenzene, and 13.75 g (0.118 mol.) TMEDA. The charge vessel and transfer line to the reactor was flushed with a 50 g portion of ethylbenzene. Next 13.44 ml (0.0269 mole) 2.0 M n-butyllithium was transferred through the charge vessel to the reactor followed by a 50 g aliquot of ethylbenzene. The reactor was heated to 65° C. Agitation was then increased to 1130 RPM and the reactor purged of N₂ by pressuring to 65 PSIG with dry H₂ (through the headspace) and venting three times (slowly venting to keep the contents from foaming out of the reactor). The H₂ regulator was set to 15 PSIG and 1050 g (10.08 mol.) styrene was fed through a subsurface feed line (0.01″ ID tip, 5.2 ft/s) against the hydrogen head pressure over a period of 240 minutes controlling the temperature at 67° C.-68° C. At the end of the styrene feed, the monomer feed line to the reactor, including the alumina columns, were flushed with 50 ml of anhydrous cyclohexane. The styrene feed and flush to the reactor was deemed complete when no further heat of reaction was observed generally signified by the permanent closing of the automated control valve on the coiling coils. During the course of the run the valve to the hydrogen regulator was periodically closed to verify uptake of hydrogen during the styrene feed. After 80-90% of the styrene feed had been completed, hydrogen up take had slowed considerably.

The unquenched content of the reaction mixture was transferred to the wash reactor and then washed following the Standard Workup Procedure. During the transfer of the unquenched reaction mixture a 10 ml sample of the reaction mixture is obtained for analysis. The sample is red in color and transparent to light giving it an appearance similar to the color of a living APS process sample. The sample's appearance is completely unlike the characteristic dark black-red (black cherry) color of samples anionic chain transfer polymerization conducted in the absence of a hydrogen atmosphere. Such samples of SASH catalyst where the catalyst components are combined under N₂ before forming the hydride generally can contain large (mm size) catalyst particles. The sample is quenched by the addition of a drop of methanol which immediately quenches the red color and results in the immediate formation and evolution of hydrogen gas. GPC Analysis of the crude quenched reaction mixture was as follows: M_(n): 560, M_(w): 914, M_(z): 1344, PD: 1.63, σ_(n)=445, _(n)α₃=2.03.

The product was then isolated following the Standard Product Isolation Procedure to yield 1050 g of a SASH PS distribution having GPC MWD of M_(n): 357, M_(w): 545, M_(z): 936, PD: 1.53, σ_(n)=259, _(n)α₃=3.72. A second WFE operation. (0.1-0.3 mmHg vacuum, 172.5° C., 60% of full wiper speed, feeding at 1.0 liters/hr) provided 925.0 of a SASH PS distribution having 0.99 GPC area % styrene dimer content and a GPC MWD of M_(n): 728, M_(w): 1019, M_(z): 1380, PD: 1.40, σ_(n)=460, _(n)α₃=1.80.

Upon completion of the run the autoclave reactor was rinsed with standard drum grade (not anhydrous) ethylbenzene, purged well with nitrogen and then opened for inspection. Although the heated reactor walls were generally free of solids, however, the cold surfaces (i.e. cooling coils, agitator assembly, dip leg, monomer feed-line and thermowell) were heavily coated with red crystalline solids up to solvent line demarking the initial reactor stirred content volume—i.e. the height or level of stirred reaction medium formed prior to charging hydrogen and styrene.

Examples 20-28

The experimental details of Examples 20-28 (reaction conditions, reagent charges, and initial as well as final catalyst concentration), scale-up parameters (relative feeds and relative hourly feed rates) and results (polymer molecular weight distribution as determined by GPC and polymer yield) are presented in tabular form in Table V. Because these Examples feature recycle oligomer (comprised mainly of dimer>90%) recovered from a previous run or runs, GPC MWD are reported only for the crude product distribution excludes the styrene dimer content. Product yields in excess of 100% represent a net incorporation of the organic chain transfer agent, which in these examples is ethylbenzene. In general the amount of dimer recovered was ≈100% less to ≈80% more than that which was charged in the recycle. Product yields of less than 100% represent a net production of ethylbenzene and/or dimer. SASH Catalyst Example 24 resulted in a 102% yield of the SASH PS polymer distribution and a 100% yield on the dimer stripped SASH PS product distribution. Example 24 which utilized 93.5 g of recovered dimer stream having GPC M_(n)=234, provided 120 g of recovered dimer with M_(n)=215. Thus Example 14 and the other 8 Examples presented in Table V very well demonstrate high yield hydrogen mediated saline hydride initiated styrene polymerization process. Example 24 is representative of the practice of the 9 Examples of Table IV. Thus Example 24 is described in greater detail below.

Example 24 Representative of Full Scale Monomer Feed Volume for SASH Catalyst w/Recycle Oligomer at Moderate Temperatures 70° to 75° C.

An anhydrous solvent mixture comprised of ethylbenzene 154.76 g (1.46 mol), 126.84 g cyclohexane, and 93.46 g styrene oligomer mix (M_(n)=234, 0.043 mole) was charged to the reactor at 23° C. under a dry nitrogen atmosphere. To the stirred solvent (800 RPM, twin pitch blade impellers, blade placement Configuration I) was charged through the charge vessel a solution previously formed from 3.51 g (0.0313 mol.) potassium t-butoxide, 51.5 g (0.49 mol.) ethylbenzene, and 15.98 g (0.138 mol.) TMEDA. The charge vessel and transfer line to the reactor was flushed with a 30 ml portion of anhydrous cyclohexane. Next 15.63 ml (0.0313 mole) 2.0 M n-butyllithium was transferred through the charge vessel to the reactor followed by a 25 g aliquot of cyclohexane. Agitation was then increased to 1130 RPM and the reactor purged of N₂ by pressuring to 65 PSIG with dry H₂ (through the headspace) and venting three times (slowly venting to keep the contents from foaming out of the reactor). The H₂ regulator was set to 20 PSIG and the reactor heated to 72° C. while feeding 1172 g (11.26 mol.) styrene. The styrene was fed through a subsurface feed line (0.01″ ID tip, 5.3 ft/s) against the hydrogen head pressure over a period of 263 minutes controlling the reaction temperature at 72° C. At the end of the styrene feed, the monomer feed line to the reactor, including the alumina columns, were flushed with 50 ml of anhydrous cyclohexane. The styrene feed and flush to the reactor was deemed complete when no further heat of reaction was observed generally signified by the permanent closing of the automated control valve on the coiling coils. During the course of the run the valve to the hydrogen regulator was periodically closed to verify uptake of hydrogen during the styrene feed. After ca.75% of the styrene feed had been completed, hydrogen up take had slowed considerably.

The unquenched content of the reaction mixture was transferred to the wash reactor and then washed following the Standard Workup Procedure. During the transfer of the unquenched reaction mixture a 10 ml sample of the reaction mixture was obtained for analysis. The sample was red to dark red in color and transparent to light with little to no settled or suspended solids. The sample was quenched by the addition of a drop of methanol which immediately quenches the red color and results in the immediate formation and evolution of hydrogen gas. GPC Analysis of the crude quenched reaction mixture excluding the dimer content was as follows: M_(n): 744, M_(w): 1045, M_(z): 1390, PD: 1.40, σ_(n)=473, _(n)α₃=1.59.

The product was then isolated following the Standard Product Isolation Procedure to yield 1289 g SASH PS distribution (SASH PS distribution) having GPC MWD excluding dimer of M_(n): 770, M_(w): 1096, M_(z): 1490, PD: 1.42, σ_(n)=501, _(n)α₃=1.76. A second WFE operation (0.1-0.3 mmHg vacuum, 172.5° C., 60% of full wiper speed, feeding at 1.0 liters/hr) provided 1169 g of a SASH PS distribution having 0.60 GPC area % styrene dimer content and a GPC MWD of M_(n): 750, M_(w): 1053, M_(z): 1395, PD: 1.40, σ_(n)=477, _(n)α₃=1.56.

Upon completion of the run the autoclave reactor was rinsed with standard drum grade (not anhydrous) ethylbenzene, purged well with nitrogen and then opened for inspection. The heated reactor walls and the cold surfaces (i.e. cooling coils, agitator assembly, dip leg, monomer feed-line and thermowell) generally free of crystalline solids. A small amount of red crystalline solids did adhere to the monomer feed line drip tip. It is deemed that based on this experiment and the others like it that the presence of monomer in significant quantities suppresses crystallization of the TMEDA complexed organopotassium anions formed under the nitrogen atmosphere prior to reduction with hydrogen to form the SASH catalyst.

Examples 29-36

The experimental details of Examples 29-36 (reaction conditions, reagent charges, and initial as well as final catalyst concentration), scale-up parameters (relative feeds and relative hourly feed rates) and results (polymer molecular weight distribution as determined by GPC and polymer yield) are presented in tabular form in Table VI.

Example 29 Partial Monomer Feed to Form SASH Catalyst from a Living Anionic Polystyrene Distribution

Anhydrous cyclohexane 300 ml, was charged to the reactor at 19° C. under a dry nitrogen atmosphere. To the stirred solvent (800 RPM, twin pitch blade impellers, blade placement Configuration I) was sequentially charged through the charge vessel 0.64 g (0.0325 mole) TMEDA in 50 ml cyclohexane followed by 16.27 ml (0.0325 mole) 2.0 M n-butyllithium and followed by 50 ml cyclohexane to flush the charge vessel and lines to the reactor. Styrene, 25 g of the total charge of 316.4 g (3.04 mol), was fed over 2.8 minutes (10 ml/min) to the TMEDA:butyllithium initator to form the living APS composition. The styrene metering pump was then set to 0.25 ml/min and the feed was continued at the reduced rate while a solution previously formed from 3.63 g (0.0324 mol.) potassium t-butoxide, 109 ml cyclohexane, and 18.96 g (0.137 mol.) TMEDA was charged to the reactor. The charge vessel and transfer line to the reactor was flushed with a 50 ml portion of cyclohexane. Agitation was then increased to 1130 RPM and the reactor purged of N₂ by pressuring to 65 PSIG with dry H₂ (through the headspace) and venting three times (slowly venting to keep the contents from foaming out of the reactor). The H₂ regulator was set to 72 PSIG and the reactor heated to 72° C. while feeding the remainder of the styrene at a feed rate of 4.93 ml/min. The bulk of the styrene was fed through a subsurface feed line (0.01″ ID tip, 5.3 ft/s) against the hydrogen head pressure over total feed time of ≈71 minutes controlling the reaction temperature at 72° C. At the end of the styrene feed, the monomer feed line to the reactor, including the alumina columns, were flushed with 50 ml of anhydrous cyclohexane. The styrene feed and flush to the reactor was deemed complete when no further heat of reaction was observed generally signified by the permanent closing of the automated control valve on the coiling coils.

The unquenched polymerization reaction mixture was transferred with positive H₂ pressure to the wash vessel previously heated (N₂ atmosphere) and previously charged with 300 ml of deoxygenated water along with 100 ml of recovered cyclohexane distilled from previous runs. Thus the reaction mixture is quenched with care in the wash reactor. The transfer however for this Example and the next five Examples (Examples 30-34) of Table VI was through the dip leg sample port thus leaving 100 ml or approximately 82 g of reaction mixture in the reactor. The reaction heel thus formed was then used in the subsequent run to form the catalyst. Only for Example 35 was the entire content of the reactor transferred to the wash reactor and thereby completing this set of Examples. The quenched reaction mixture from Example 29 was discarded and not used to form the composite of the other 6 runs.

During the transfer of the unquenched reaction mixture a 10 ml sample of the reaction mixture was obtained for analysis. The sample was light pink (pink lemonade to under ripe water melon) in color and transparent to light with a small content suspended solids. The sample was quenched by the addition of a drop of methanol which immediately quenches the pink color and results in the instantaneous formation and evolution of hydrogen gas. The suspended solids appear to continue to produce or liberate hydrogen for a short period of time. GPC Analysis of the crude quenched reaction mixture was as follows: M_(n): 351, M_(w): 706, M_(z): 1331, PD: 1.40, σ_(n)=353, _(n)α₃=3.53. It should be noted that this GPC MWD was bimodal having a high molecular weight fraction with M_(n): 1330, M_(w): 1480, M_(z): 1680, PD: 1.12, σ_(n)=447, _(n)α₃=1.776 that made up about 35 GPC area % of the dimer and above composition, most of the composition was ethylbenzene.

Examples 30 and 31 Representative of Full Scale Monomer Feed Volume for SASH Catalyst Runs in Cyclohexane with SASH Catalyst Formed w/o Added Organic Chain Transfer Agent 72° C. Runs

To the heel from the previous Example was charged 250 ml of anhydrous cyclohexane at 30° C. to the reactor under a hydrogen atmosphere (0 PSIG). To the stirred reaction mixture (1130 RPM, twin pitch blade impellers, the first at the bottom of the stirrer shaft and the second placed 5.0 inches above the first) was charged through the charge vessel a solution previously formed from 3.63 g (0.0324 mol.) potassium t-butoxide, 109 ml cyclohexane and 19.6 g (0.169 mol.) TMEDA. The charge vessel and transfer line to the reactor was flushed with a 50 ml portion of cyclohexane. Next 16.11 ml (0.0322 mole) 2.0 M n-butyllithium was transferred through the charge vessel to the reactor followed by a 50 ml aliquot of cyclohexane. Trace N₂, introduced the charging the catalyst components, was purged by pressuring to 50 PSIG with dry H₂ (through the headspace) and venting three times (slowly venting to keep the contents from foaming out of the reactor). The H₂ regulator was set to 72 PSIG, the reactor was heated to 72° C. while 912.4 g (8.76 mol.) styrene was fed through a subsurface feed line (0.01″ ID tip, 5.3 ft/s) against the hydrogen head pressure over a period of 205 minutes maintaining the reactor at 72° C. At the end of the styrene feed, the monomer feed line to the reactor, including the alumina columns, were flushed with 50 ml of anhydrous cyclohexane. The styrene feed and flush to the reactor was deemed complete when no further heat of reaction was observed generally signified by the permanent closing of the automated control valve on the coiling coils. During the course of the run the valve to the hydrogen regulator was periodically closed to verify uptake of hydrogen during the styrene feed. After about 66% of the styrene feed had been completed, hydrogen up take had slowed considerably vs. the initial amount but uptake did continue at a sufficient rate until the end of the styrene monomer feed.

The unquenched polymerization reaction mixture was transferred with positive H₂ pressure to the wash vessel previously heated 65° C. (N₂ atmosphere) and previously charged with 300 ml of deoxygenated water and left to stir. The transfer of the crude reaction mixture was through the dip leg sample port thus leaving 100 ml, or approximately 82 g, of reaction mixture in the reactor for the next run. The reactor was then charged with 250 ml of anhydrous cyclohexane and cooled to 30° C. while stirring at 400 rpm under a 65 psig hydrogen atmosphere.

For Example 31 the SASH styrene polymerization process was repeated exactly to within minor experimental differences as above for Example 30. Upon completion of the run, the content of the reactor was transferred through the dip leg sample port to the heated (65° C.) and stirred quenched reaction mixture from Example 30 with the 300 ml aqueous solution previously formed. A 100 ml heel of Example 31 that was left behind was combined with 250 ml of anhydrous cyclohexane and cooled to 30° C. for the next Example in this series of runs.

The combined quenched reaction mixtures formed from Examples 30 and 31 were water washed (3×300 ml) with deoxygenated water, concentrated by distilling cyclohexane, TMEDA and the Ethylbenzene formed in the process until a pot temperature of 135° C. was reached. Upon cooling these samples were collected and set aside to later combine with washed and stripped product mixtures formed from Examples 32 and 33 and Examples 34 and 35.

During the transfers of the unquenched reaction mixtures of Examples 30 and 31, 10 ml samples of each reaction mixture were obtained for analysis. The samples were light pink in color and transparent to light with a small content suspended solids. The samples when quenched by the addition of a drop of methanol immediately evolved hydrogen gas and became colorless. GPC analyses of Examples 30 and 31 crude quenched reaction mixture was as follows: Ex. 30. M_(n): 401, M_(w): 637, M_(z): 1067, PD: 1.59, σ_(n)=308, _(n)α₃=3.24; Ex. 31: M_(n): 423, M_(w): 659, M_(z): 1025, PD: 1.59, σ_(n)=316, _(n)α₃=2.64. Thus the compositions were nearly identical in molecular weight with Example 30 having a slightly increased asymmetry from the M_(w)=1480 Dalton APS artifact from Example 29.

Example 36 Blending, Ethylbenzene and Dimer Recovery by Wiped Film Evaporation of Said Composite

A composite blend was formed from the combined washed and stripped product mixtures of Examples 30 and 31, Examples 32 and 33 and Examples 34 and 35. This was accomplished by adding said washed and stripped blends of Examples 30 and 31, Examples 32 and 33 back the wash reactor containing the washed and stripped blend of Examples 34 and 35 at 100° C. After blending the product solution was allowed to cool before collecting 4857.99 of solution. The product solution was then further stripped of ethylbenzene and TMEDA with the use of a wiped film evaporator (WFE, 2″ glass Pope Still, operated at 50.0 mmHg vacuum, 140° C., 60% of full wiper speed, feeding at 1.0 liters/hr). This first WFE operation produced 2986.7 g (61.5% Yield styrene dimer and above) SASH PS distribution having GPC MWD of M_(n): 428, M_(w): 663, M_(z): 1050, PD: 1.55, σ_(n)=317, _(n)α₃=2.83. A second WFE operation. (0.1-0.3 mmHg vacuum, 172.5° C., 60% of full wiper speed, feeding at 1.0 liters/hr) provided 2332.7 (50% yield) of a SASH PS distribution having 1.4 GPC area % styrene dimer content and a GPC MWD of M_(n): 558, M_(w): 763, M_(z): 1100 PD: 1.40, σ_(n)=477, _(n)α₃=1.56. Also recovered from the second WFE operation was 642.18 g of a styrene oligomer composition having M_(n): 213, M_(w): 220, M_(z): 227 PD: 1.031.

Upon completion of the series of 7 runs (Examples 29-35) the autoclave reactor was rinsed with standard drum grade (not anhydrous) cyclohexane, purged well with nitrogen and then opened for inspection. The heated reactor walls and the cold surfaces (i.e. cooling coils, agitator assembly, dip leg, monomer feed-line and thermowell) generally free of crystalline solids. However, a small deposit of water soluble white powdery solids adhered to the heated walls of the polymerization reactor.

Examples 37-43

The experimental details of Examples 37-43 (reaction conditions, reagent charges, and initial as well as final catalyst concentration), scale-up parameters (relative feeds and relative hourly feed rates) and results (polymer molecular weight distribution as determined by GPC and polymer yield) are presented in tabular form in Table VII. Examples 37-42 were conducted in a manner analogous to Example 14 presented in detail above. It is clear from the results of these Examples that these represent less preferred embodiments of the present invention. It should be understood that Example 37 employs an organic chain transfer agent, m-xylene, and as a consequence produces a polystyrene composition in which a significant portion of the composition is initiated with m-xylene as well as the portion initiated with the SASH catalyst. Example 38 indicates at least for this polymerization temperatures as low as 35° C. are less preferred. Examples 39-42 demonstrate that both sodium and lithium are less preferred forms of SASH catalyst for forming low molecular weight anionic chain transfer polystyrene distributions. Example 43 is described in greater detail below.

Example 43 Monometallic Lithium SASH Catalyst Process

Anhydrous ethylbenzene 300 g, was charged to the reactor at 20° C. under a hydrogen atmosphere (0 PSIG). To the stirred solvent (800 RPM, twin pitch blade impellers, blade placement Configuration III) was charged through the charge vessel a solution previously formed from 3.62 g (0.0489 mol.) of tert-butyl alcohol, 69.9 g (0.66 mol.) of ethylbenzene, and 23.50 g (0.202 mol.) of TMEDA. The charge vessel and transfer line to the reactor was flushed with a 50 g portion of ethylbenzene. Agitation was increased to 1130 RPM and then 54.10 ml (0.11 mole) of 2.0 M n-butyllithium dissolved in 100 g of ethylbenzene was transferred slowly through the charge vessel to the reactor. The reactor temperature rose 5° C. to 25° C. and the pressure increased to 2 PSIG then dropped to −4 PSIG drawing the butyllithium solution and a subsequent 50 g rinse aliquot of ethylbenzene into the reactor. The reactor containing a total of 570 g (5.4 mol.) of ethylbenzene was heated to 90° C. Trace N₂ introduced during the catalyst component charge was purged by pressuring to 50 PSIG with dry H₂ (through the headspace) and venting three times.(slowly venting to keep the contents from foaming out of the reactor). The H₂ regulator was set initially to 21 PSIG. Styrene, 462.2 g (4.44 mol.), was fed through a subsurface feed line (0.02″ ID tip, 1.2 ft/s) against the hydrogen head pressure over a period of 116 minutes controlling the temperature at 90° C. and gradually increasing the hydrogen pressure to 41 PSIG. At the end of the styrene feed, the monomer feed line to the reactor, including the alumina columns, were flushed with 50 ml of anhydrous cyclohexane. The styrene feed and flush to the reactor was deemed complete when no further heat of reaction was observed generally signified by the permanent closing of the automated control valve on the coiling coils. During the course of the run the valve to the hydrogen regulator was periodically closed to verify uptake of hydrogen during the styrene feed. The reaction did take up hydrogen albeit very slowly.

The unquenched content of the reaction mixture was transferred to the wash vessel (N₂ atmosphere) previously charged with 300 ml of deoxygenated water heated to 65° C. and then washed with deoxygenated water (3×300 ml). This reaction mixture was then properly discarded upon separation of the aqueous quench. During the course of the transfer of the unquenched reaction mixture, a 10 ml aliquot of the unquenched reaction mixture was obtained. This colorless sample was full of uniformly suspended extremely finely divided solids. The sample was quenched with methanol resulting in the immediate production and evolution of hydrogen gas from the viscous mixture. GPC analyses of the sample using standard higher molecular weight columns and polystyrene standards was as follows: GPC MWD of M_(n): 1030, M_(w): 5635, M_(z): 10,066 PD: 5.47, σ_(n)=2178, _(n)α₃=4.13.

Examples 44-60

The experimental details of Examples 44-51 and Examples 52-60 (reaction conditions, reagent charges, and initial as well as final catalyst concentration), scale-up parameters (relative feeds and relative hourly feed rates) and results (polymer molecular weight distribution as determined by GPC and polymer yield) are presented in tabular form in Table VI and Table VII respectively. Examples 44-57 feature the use of recycle oligomer (comprised mainly of dimer>90%) recovered from a previous run or runs in forming the reaction mixture. Therefore for all the Examples 44-60 in order to simplify comparison of one Example to another, the GPC MWDs that are reported for the crude product distributions exclude the styrene dimer content. Product yields in excess of 100% represent a net incorporation of the organic chain transfer agent, which in these examples is ethylbenzene. In general the amount of dimer recovered was more than that which was charged in the recycle. Product yields of less than 100% represent a net production of ethylbenzene and/or dimer. SASH Catalyst Example 60 resulted in a 105% yield of the SASH PS polymer distribution and a 89% yield on the dimer stripped SASH PS product distribution. These Examples demonstrate that with uniform or near uniform hydrogen transfer to the condensed phase, temperatures above 75° C. are preferred such that organic chain transfer more successfully competes with chain transfer involving hydrogen. Among the inventive feature of this series of Examples is the relatively slow (15-20 minute) feed of the organolithium reagent under hydrogen atmosphere. This technique or charge protocol provides the most reproducible catalyst activity and run to run reproducibility. Examples 54 in combination with 55 as well as Example 60 are described in greater detail below.

Examples 54 and 55

Representative of Full Scale Monomer Feed Volume with Dimer Recycle for SASH Catalyst at 80° C.

A reaction solvent comprising anhydrous ethylbenzene, 336 ml (290.9 g, 2.74 mole) and a styrene oligomer mixture, 154 ml (M_(n)=227, 143.0 g. 0.63 mole) was formed to yield ca. 490 ml total. Of the solvent mixture 340 ml was charged to the reactor at 20° C. under a dry hydrogen (0 PSIG H₂) atmosphere. To the stirred solvent (800 RPM, three pitched blade turbines with Configuration III above) was charged through the charge vessel via positive nitrogen pressure, a solution previously formed from 4.01 g (0.0357 mol.) potassium t-butoxide, 69.9 g (0.66 mol) ethylbenzene, and 19.90 g (0.171 mol) of TMEDA. The charge vessel and transfer line to the reactor was flushed with a 50 ml portion of reaction solvent from the total amount above. Next, 18.91 ml (0.0378 mole) 2.0 M n-butyllithium was transferred through the charge vessel to the reactor followed by two 50 ml aliquots of the reaction solvent from the total amount above. At the outset of the 15 min feed of the organolithium reagent agitation was increased to 1130 RPM. During the organolithium charge the reactor pressure decreased to −3 PSIG. The reactor head space was purged with 50 PSIG with dry H₂ (through a subsurface feedline) and venting three times (slowly venting to keep the contents from foaming out of the reactor). The H₂ regulator was set to 18 PSIG and the reactor heated to 80° C. while feeding 1038.8 g (9.97 mol.) styrene. The styrene was fed through a subsurface feed line (0.02″ ID tip, 1.88 ft/s) against the hydrogen head pressure over a period of 163 minutes controlling the reaction temperature at 80° C. At the end of the styrene feed, the monomer feed line to the reactor, including the alumina columns (acidic alumina), were flushed with 50 ml of anhydrous ethylbenzene. The styrene feed and flush to the reactor was deemed complete when no further heat of reaction was observed generally signified by the permanent closing of the automated control valve on the coiling coils. During the course of the run the valve to the hydrogen regulator was periodically closed to verify uptake of hydrogen during the styrene feed. It was observed that for a brief period 62±10 min (ca. 41% of the styrene fed, 935 g of total reaction mass in reactor) the hydrogen uptake had slowed. However the hydrogen uptake was completely restored after a total of 508 g of the styrene (ca. 50% of the total styrene fed or ca. 1050 g of reaction mass in reactor) feed had been completed. Hydrogen uptake remained generally constant throughout the rest of the feed.

The unquenched polymerization reaction mixture was transferred with positive H₂ pressure to the wash vessel previously heated (N₂ atmosphere) and previously charged with 300 ml of deoxygenated water. Thus the reaction mixture is quenched with care in the wash reactor. The above process was repeated as Example 55 with the identical charges and conditions to within minor run to run variations in measuring out the reagents and reproducing the conditions.

During the transfer of the unquenched reaction mixtures (Examples 54 and 55) 10 ml samples of the individual reaction mixtures were obtained for analyses. The samples were red to in color and transparent to light with no settled or suspended solids. The samples were quenched by the addition of a drop of methanol from a transfer pipet. The methanol immediately quenches the red color and results in the immediate formation and evolution of hydrogen gas. GPC Analysis of the crude quenched reaction mixtures excluding the dimer content was as follows: Example 54 M_(n): 533, M_(w): 681, M_(z): 892, PD: 1.278, σ_(n)=281, _(n)α₃=2.086; Example 55 M_(n): 555, M_(w): 722, M_(z): 961, PD: 1.301, σ_(n)=304, _(n)α₃=2.100; thus demonstrating the robustness and run to run reproducibility of this SASH process of this invention.

The two phase product mixture formed from Examples 54 and 55 and the quench water was heated to 76° C. and then the phases were separated. Phase cuts were easily made at 76° C., and were rapid requiring little settling time. Water and any rag or emulsion was removed through the bottom drain valve. The pH of the wash water removed from the reactor was monitored, the first wash invariably had pH=14. Additional deoxygenated water washes (2×350 ml) were conducted until the removed water wash phase had a pH 10 indicating that all alkali metal had been removed. The water washed product mixture was stripped in the wash reactor of cyclohexane, TMEDA and ethylbenzene by normal distillation while gradually heating the wash reactor's jacket temperature to 165° C. The distillation was deemed complete when the pot temperature reached a temperature above 140° C. The solution was allowed to cool before collecting 3271 g of solution. The solution was then further stripped of ethylbenzene and TMEDA with the use of a wiped film evaporator (WFE, 2″ glass Pope Still, operated at 50.0 mmHg vacuum, 140° C., wiper speed 60% of full rate, feeding at 1.0 liters/hr). This first WFE operation produced 2299.8 g SASH PS distribution having GPC MWD including dimer of M_(n): 416, M_(w): 610, M_(z): 884, PD: 1.466, σ_(n)=284, _(n)α₃=2.251; excluding dimer of M_(n): 547, M_(w): 705, M_(z): 932, PD: 1.289, σ_(n)=294, _(n)α₃=2.122. A second WFE operation (0.1-0.3 mmHg vacuum, 172.5° C., wiper speed 60% of full rate, feeding at 1.0 liters/hr) provided 1790 g of a SASH PS distribution having 0.62 GPC area % styrene dimer content and a GPC MWD of M_(n): 559, M_(w): 719, M_(z): 941, PD: 1.29, σ_(n)=299, _(n)α₃=2.00.

Example 60 Representative of Full Scale Monomer Feed Volume for SASH Catalyst at 90° C.

Anhydrous ethylbenzene, 337 ml of 487 ml total, (422.13 g, 3.98 mol) was charged to the reactor at 20° C. under a dry hydrogen (3 PSIG H₂) atmosphere. To the stirred solvent (800 RPM, three pitched blade turbines with Configuration III above) was charged through the charge vessel via positive nitrogen pressure, a solution previously formed from 3.75 g (0.0324 mol.) potassium t-butoxide, 69.9 g (0.67 mol) ethylbenzene, 17.90 g (0.154 mol) of TMEDA. The charge vessel and transfer line to the reactor was flushed with a 50 ml portion of anhydrous ethylbenzene from the total amount above. Next, 21.88 ml (0.0438 mole) 2.0 M n-butyllithium was transferred through the charge vessel to the reactor followed by two 50 ml aliquots of anhydrous ethylbenzene from the total amount above. At the outset of the 15 min feed of the organolithium reagent agitation was increased to 1130 RPM. During the organolithium charge the reactor pressure decreased to 0 PSIG. The reactor head space was purged with 50 PSIG with dry H₂ (through a subsurface feedline) and venting three times (slowly venting to keep the contents from foaming out of the reactor). The H₂ regulator was set to 23 PSIG and the reactor heated to 90° C. while feeding 1044.9 g (10.03 mol.) styrene. The styrene was fed through a subsurface feed line (0.02″ ID tip, 2.02 ft/s) against the hydrogen head pressure over a period of 153 minutes controlling the reaction temperature at 90° C. At the end of the styrene feed, the monomer feed line to the reactor, including the alumina columns, were flushed with 50 ml of anhydrous ethylbenzene. The styrene feed and flush to the reactor was deemed complete when no further heat of reaction was observed generally signified by the permanent closing of the automated control valve on the coiling coils. During the course of the run the valve to the hydrogen regulator was periodically closed to verify uptake of hydrogen during the styrene feed. It was observed that for a brief period 60±10 min (ca. 41% of the styrene fed, 910 g of total reaction mass in reactor) the hydrogen uptake had slowed. However the hydrogen uptake was completely restored after a total of 510 g of the styrene (ca. 50% of the total styrene fed or ca. 1000 g of reaction mass in reactor) feed had been completed. Hydrogen uptake remained generally constant throughout the rest of the feed.

The unquenched polymerization reaction mixture was transferred with positive H₂ pressure to the wash vessel previously heated (N₂ atmosphere) and previously charged with 300 ml of deoxygenated water. Thus the reaction mixture is quenched with care in the wash reactor. This two phase product mixture was heated to 76° C. and then the phases were separated. Phase cuts were easily made at 76° C., and were rapid requiring little settling time. Water and any rag or emulsion was removed through the bottom drain valve. The pH of the wash water removed from the reactor was monitored, the first wash invariably had pH=14. Additional deoxygenated water washes (2×300 ml) were conducted until the removed water wash phase had a pH 10 indicating that all alkali metal had been removed.

During the transfer of the unquenched reaction mixture a 10 ml sample of the reaction mixture was obtained for analysis. The sample was red to dark red in color and transparent to light with little to no settled or suspended solids. The sample was quenched by the addition of a drop of methanol which immediately quenches the red color and results in the immediate formation and evolution of hydrogen gas. GPC Analysis of the crude quenched reaction mixture was as follows: GPC MWD including dimer of M_(n): 474, M_(w): 718, M_(z): 1070, PD: 1.516, σ_(n)=340, _(n)α₃=2.369; excluding dimer of M_(n): 590, M_(w): 795, M_(z): 1103, PD: 1.347, σ_(n)=348, _(n)α₃=2.327. The water washed product mixture was stripped in the wash reactor of cyclohexane, TMEDA and ethylbenzene by normal distillation while gradually heating the wash reactor's jacket temperature to 165° C. The distillation was deemed complete when the pot temperature reached a temperature above 135° C. The solution was allowed to cool before collecting 1770 g of solution. The solution was then further stripped of ethylbenzene and TMEDA with the use of a wiped film evaporator (WFE, 2″ glass Pope Still, operated at 50.0 mmHg vacuum, 140° C., 60% of full wiper speed, feeding at 1.0 liters/hr). This first WFE operation produced 1100.0 g SASH PS distribution having GPC MWD including dimer of M_(n): 481, M_(v): 724, M_(z): 1070, PD: 1.506, σ_(n)=342, _(n)α₃=2.319. A second WFE operation (0.1-0.3 mmHg vacuum, 172.5° C., 60% of full wiper speed, feeding at 1.0 liters/hr) provided 932.0 g of a SASH PS distribution having 0.47 GPC area % styrene dimer content and a GPC MWD of M_(n): 605, M_(v): 812, M_(z): 1119, PD: 1.34, σ_(n)=354, _(n)α₃=2.28. Additionally 165.49 g (15.8% of styrene charged) of a styrene oligomer mixture having M_(n)=222 was recovered.

ANALYTICAL METHODS

Molecular weight distributions in terms of M_(w), M_(n), M_(z) and PD values for low molecular weight (M_(w)<1600 Daltons) were obtained by GPC using a Viscotek TDA modular system equipped with a UV detector, autosampler, pump, and temperature controlled column compartment. The columns used were Agilent Oligopore columns, 300 mm by 7.5 mm, part number 1113-6520. The solvent used was tetrahydrofuran, HPLC grade. The test procedure used entailed dissolving approximately 0.06-0.1 g of sample in 10 mL of THE. An aliquot of this solution is filtered and 200 μL is injected on the columns. Based on isolated 1,3-diphenylbutane(dimer) and 1,3,5-triphenylhexane (trimer) adducts, and the mode of separation is size exclusion, peaks are identified according to their order of elution as 1,3-diphenylbutane, 1,3,5-triphenylhexane, 1,3,5,7-tetraphenyloctane (tetramer), 1,3,5,7,9-pentaphenyldecane (pentamer), etc. The individual peaks of the oligomeric material are then assigned theoretical molecular weight values. A calibration curve is constructed using these theoretical values and their corresponding retention times. Based on this calibration, the overall distribution data is calculated and reported. The calculations were performed by the Viscotek Omnisec, version 4.2.0.237 gel permeation chromatography (GPC) data collection and processing system.

Molecular weight distributions in terms of M_(w), M_(n), M_(z) and PD values for higher molecular weight (M_(w)>1600 Daltons) were obtained by GPC using a Viscotek TDA modular system equipped with a UV detector, autosampler, pump, and temperature controlled column compartment. The following three Agilent Technologies columns were used in series to perform the separation: (1) Oligopore column, 300 mm by 7.5 mm, part number 1113-6520, (1) Mixed Bed E, 300 mm×7.5 mm, part number 1110-6300, and (1) Mixed Bed D, 300 mm×7.5 mm, part number 1110-6504. The solvent used was tetrahydrofuran, HPLC grade. The test procedure used entailed dissolving approximately 0.06-0.1 g of sample in 10 mL of THE. An aliquot of this solution is filtered and 200 μL is injected on the columns. Based on isolated 1,3-diphenylbutane(dimer) and 1,3,5-triphenylhexane (trimer) adducts, and the mode of separation is size exclusion, peaks are identified according to their order of elution as 1,3-diphenylbutane, 1,3,5-triphenylhexane, 1,3,5,7-tetraphenyloctane (tetramer), 1,3,5,7,9-pentaphenyldecane (pentamer), etc. The individual peaks of the oligomeric material are then assigned theoretical molecular weight values. A calibration curve is constructed using these theoretical values and their corresponding retention times along with the retention times of polystyrene reference standards of known molecular weight. Based on this calibration, the overall distribution data is calculated and reported. As above the calculations were performed by the Viscotek Omnisec, version 4.2.0.237 gel permeation chromatography (GPC) data collection and processing system.

TABLE III SASH catalyst in cyclohexane (CH), moderate temperature processes with high monomer to added organic chain transfer agent (ethylbenzene, EB) ratio. Patent Example 4 5 6 7 8 9 SASH Cat. Formed Temp, ° C. 23° 23° 23° 23° 23° 23° Polymerization Temp. ° C. 27 56 66 65 65 65 Reactor Atmosphere H₂ H₂ H₂ H₂ H₂ H₂ psig 25 25 19 15 19 23 Solvent CH CH CH CH CH CH Total Mass, g 725 584 390 312 390 390 Catalyst Potassium t-Butoxide, g 11.2 5.64 3.27 1.98 2.78 3.08 moles 0.0998 0.0503 0.0291 0.0176 0.0248 0.0274 Organic CTA EB EB EB EB EB EB Mass, g 1.06 5.32 3.56 22.00 20.64 20 moles 0.01 0.05 0.03 0.21 0.19 0.19 vol, ml 1.2 6.1 4.1 25 24 23 TMEDA, g 47 34.08 15 9.09 12.78 10.7 moles 0.404 0.293 0.129 0.078 0.11 0.092 vol, ml 60.65 43.97 19.35 11.73 16.49 13.81 n-Butyllithium, Molarity in CH 2 2 2 2 2 2 vol, ml 50 25.11 14.56 8.8 12.39 13.72 moles 0.1 0.0502 0.0291 0.0176 0.0248 0.0274 Styrene, g 200 730 911 1100 1032 534 moles 1.92 7.01 8.75 10.56 9.91 5.13 vol, ml 220 803 1002 1210 1135 587 feed rate ml/min 4.82 4.82 4.82 4.82 4.82 4.82 time of feed, min 46 167 208 251 236 122 feed velocity ft/sec 5.2 5.2 5.2 5.2 5.2 5.2 Process Scale-Up Parameters Total Charges initial, g. 823 649 423 352 435 434 Total Charges final, g 1023 1379 1334 1452 1467 968 Initial KH* concentration (ppm) 4900 3100 2800 2000 2300 2500 Final KH* concentration (ppm) 3900 1500 900 500 700 1100 mole TMEDA/Mol alkali metal 2.20 2.92 3.10 2.22 2.22 1.67 mole styrene/mole Li 19 140 300 600 400 187 mole sty/mole Li/hr 25 50 87 143 102 92 mole sty./mole Org. CTA 192 140 260 51 51 27 mole sty./hr/mole of Org. CTA 252 50 75 12 13 13 SASH PS Solvent Stripped polymer yield, g 125 538 677 915 902 335 yield % on monomer 63% 74% 74% 83% 87% 63% M_(n) 357 392 455 976 631 475 M_(w) 545 555 697 1869 1073 759 Mz 936 818 1044 3092 1855 1165 PD_(n) 1.53 1.42 1.53 1.91 1.7 1.6 σ_(n) 259.1 252.8 331.8 933.6 528.1 367.3 _(n)α₃ 3.72 2.64 2.37 2.65 3.24 2.43 SASH PS Dimer stripped polymer yield, g na 400 638.1 na 754.1 278.5 yield % on monomer na 55% 70% na 73% 52% M_(n) na 479 483 na 724 617 M_(w) na 628 724 na 1134 865 Mz na 861 1066 na 1615 1220 PD_(n) na 1.31 1.5 na 1.57 1.4 σ_(n) na 267 341 na 545 391 _(n)α₃ na 2.44 2.3 na 1.87 2.22

TABLE IV SASH catalyst process in ethylbenzene (EB), moderate temperature relatively low monomer to total organic chain transfer agent ratio. Example 10 11 12 13 14 15 16 17 18 19 Temp Catalyst Formed 20° 20° 20° Rxn Rxn Rxn Rxn Rxn Rxn Rxn Temperature, ° C. 65 65-70 70 70 67.5 75 75 75 70 70 Atmosphere H₂ H₂ H₂ H₂ H₂ H₂ H₂ H₂ H₂ H₂ psig 16-18 15 15 15 15 15-18 23-25 25 24-26 24-26 Solvent EB EB EB EB EB EB EB EB EB EB Total Mass, g 300 214 260 356 300 300 300 300 303.9 376 Ethylbenzene moles 2.83 2.02 2.45 3.35 2.83 2.83 2.83 2.83 2.86 3.54 Catalyst Potassium t-butoxide, g 2.95 2.96 3 4.57 3.017 2.828 3.58 3.79 2.86 2.85 moles 0.0263 0.0264 0.0267 0.0407 0.0269 0.0252 0.0319 0.0338 0.0255 0.0254 Organic CTA EB EB EB EB EB EB EB EB EB EB Mass, g 43.5 42.2 43.5 44 43.5 50 47.4 50.3 49.6 49.6 moles 0.41 0.4 0.41 0.42 0.41 0.47 0.45 0.47 0.47 0.47 vol, ml 50 49 50 51 50 58 55 58 57 57 TMEDA Mass, g 13.45 13.5 13.67 20.83 13.75 12.89 17.11 17.69 12.96 13.6 moles 0.116 0.116 0.118 0.179 0.118 0.111 0.147 0.152 0.112 0.117 vol, ml 17.35 17.42 17.64 26.88 17.74 16.63 22.08 22.83 16.72 17.55 n-Butyllithium 2.0 M CH, ml 13.15 13.2 13.37 20.34 13.44 12.6 16 16.82 13 12.71 moles 0.0263 0.0264 0.0267 0.0407 0.0269 0.0252 0.032 0.0336 0.026 0.0254 Monomer: Styrene, g 1000 1100 1050 800 1050 1050 1020 1051 1054 1059 moles 9.6 10.56 10.08 7.68 10.08 10.08 9.79 10.09 10.12 10.17 vol, ml 1100 1210 1155 880 1155 1155 1122 1156 1159 1165 feed rate ml/min 4.82 4.82 4.82 4.82 4.82 4.82 6.2 6.2 4.93 4.93 time of feed, min 228 251 240 183 240 240 181 185 237 238 feed velocity ft/sec 5.2 5.2 5.2 5.2 5.2 5.2 5.3 5.3 5.3 5.3 ProcessScale-Up Parameters Total Charge initial, g. 370 283 331 441 371 376 381 385 379 452 Total Charge final, g 1370 1383 1381 1241 1421 1426 1401 1436 1433 1511 Initial KH* conc. ppm 2850 3744 3245 3698 2908 2692 3373 3506 2749 2256 Final KH* conc. ppm 770 766 777 1315 759 709 916 940 728 675 mole styrene/mole Li 365 400 377 189 375 400 306 300 389 400 mole sty/mole Li/hr 96 96 94 62 94 100 101 97 99 101 mole sty./mole Org. CTA 2.97 4.38 3.53 2.04 3.12 3.06 2.99 3.06 3.04 2.54 mole styr/hr/mole Org. CTA 0.78 1.05 0.88 0.67 0.78 0.77 0.99 0.99 0.77 0.64 SASH PS Solv. Strip. 943 1033 1077 828 1050 1108 1083 1133 1150 1113 polymer yield, g yield % on monomer 94% 94% 103% 103% 100% 106% 106% 108% 109% 105% M_(n) 467 507 512 367 560 534 485 422 526 583 M_(w) 720 815 794 497 914 829 735 601 848 1056 Mz 1073 1225 1166 695 1344 1193 1091 871 1253 1588 PD_(n) 1.54 1.61 1.55 1.35 1.63 1.55 1.52 1.42 1.61 1.81 σ_(n) 344 395 380 218 445 397 348 275 412 525 _(n)α₃ 2.3 2.24 2.15 2.38 2.03 1.98 2.33 2.41 2.1 2.05 SASH PS Dimer Strip. 817 891 958 609 925 978 929 919 1011 1022 polymer yield, g yield % on monomer 82% 81% 91% 76% 88% 93% 91% 87% 96% 97% M_(n) 575 629 615 486 728 662 607 540 683 801 M_(w) 805 895 859 593 1019 917 798 684 942 1197 Mz 1126 1248 1181 750 1380 1243 1058 891 1280 1665 PD_(n) 1.4 1.42 1.40 1.22 1.40 1.39 1.31 1.27 1.38 1.49 σ_(n) 364 409 387 228 460 411 340 279 421 563 _(n)α₃ 2.14 2.02 1.97 2.15 1.8 1.86 1.97 2.11 1.91 1.79

TABLE V SASH catalyst process in mixed solvent systems ethylbenzene (EB) with or without cyclohexane with recycle dimer oligomer mixture. Patent Example 20 21 22 23 24 25 26 27 28 Temp Catalyst Formed 23° 23° 23° 23° 23° 23° 23° 23° 23° Rxn. Temperature, ° C. 75 75 75 70 72 72 72 72 72 Atmosphere H₂ H₂ H₂ H₂ H₂ H₂ H₂ H₂ H₂ psig 16-18 18-20 21-25 25 20 20 20-30 20-30 20-30 Solvent EB EB EB EB & CH EB & CH EB & CH EB & CH EB & CH EB & CH Solvent mass, g 216 175 179.6 294 281.6 240.1 238 241.9 238 Contained Ethylbenzene moles 2.03 1.65 1.69 1.54 1.46 0.85 0.85 0.86 0.85 Recyle oligomer M_(n) 210 210 215 209 234 199 199 199 199 Mass, g 100.6 138 145.07 63.15 93.46 93.85 96.01 92.09 96.01 moles 0.48 0.66 0.67 0.3 0.4 0.47 0.48 0.46 0.48 Catalyst Potassium t-Butoxide, g 2.828 2.662 2.52 3.12 3.51 3.078 3.13 3.08 3.18 moles 0.0252 0.0237 0.0225 0.0278 0.0313 0.0274 0.0279 0.0274 0.0283 EB, g 50 42 47.4 51.6 51.5 51.5 58.5 61.6 53.6 moles 0.47 0.4 0.45 0.49 0.49 0.49 0.55 0.58 0.51 vol, ml 58 48 55 60 59 59 67 71 62 TMEDA, g 12.89 12.13 11.45 14.25 15.98 15.98 14.2 15.62 15.32 moles 0.111 0.104 0.099 0.123 0.138 0.138 0.122 0.134 0.132 vol, ml 16.63 15.65 14.77 18.39 20.62 20.62 18.32 20.15 19.77 n-Butyllithium, Molarity 2 2 2 2 2 2 2 2 2 vol, ml 12.6 11.86 11.2 13.6 15.63 13.91 14.81 14.81 14.81 moles 0.0252 0.0237 0.0224 0.0272 0.0313 0.0278 0.0296 0.0296 0.0296 Monomer: Styrene, g 1057 1055 1057 1011.4 1172.5 1011 1019 1003.2 1006 moles 10.15 10.13 10.15 9.71 11.26 9.71 9.78 9.63 9.66 vol, ml 1163 1161 1163 1113 1290 1112 1121 1104 1107 feed rate ml/min 4.82 4.82 4.82 4.93 4.93 4.93 4.93 4.93 4.93 time of feed, min 241 241 241 227 263 227 229 225 226 feed rate g/min 4.38 4.38 4.38 4.45 4.45 4.45 4.45 4.45 4.45 feed velocity ft/sec 5.2 5.2 5.2 5.3 5.3 5.3 5.3 5.3 5.3 Process Scale-Up Parameters Total Charge initial, g. 389 376 392 434 455 412 418 423 414 Total Charge final, g 1446 1431 1449 1445 1627 1423 1437 1426 1420 Initial KH* conc. ppm 2597 2528 2291 2516 2758 2707 2841 2811 2867 Final KH* conc. ppm 699 665 620 755 771 784 827 833 836 mole styrene/mole Li 403 427 453 357 360 349 330 325 326 mole sty/mole Li/hr 100 106 113 94 82 92 87 87 87 mole sty./mole Org. CTA 3.4 3.75 3.61 4.17 4.81 5.36 5.21 5.06 5.27 mole styr/hr/mole Org. CTA 0.85 0.93 0.9 1.1 1.1 1.42 1.36 1.35 1.4 SASH PS Solv. Strip, poly. 1074 1070 1105 1065 1289 2162² 2257² yield, g yield % on monomer¹ 102% 101% 105% 99% 102% 98% 103% M_(n) 590 599 640 784 744 649 694 685 605 M_(w) 772 791 869 1165 1045 990 1045 1012 889 Mz 1026 1058 1176 1620 1390 1383 1439 1375 1219 PD_(n) 1.31 1.32 1.36 1.49 1.4 1.52 1.51 1.48 1.47 σ_(n) 328 339 383 547 473 470 494 473 414 _(n)α₃ 2.04 2.04 1.97 1.81 1.59 1.77 1.68 1.62 1.72 SASH PS Dimer Strip. 993 1034.5 1040.3 955.29 1169 1909 1969.17 polymer yield, g yield % on monomer¹ 94% 98% 98% 94% 100% 94% 98% M_(n) 596 598 644 800 750 750 724 M_(w) 769 783 875 1193 1053 1085 1011 Mz 990 1013 1181 1651 1395 1508 1364 PD_(n) 1.29 1.309 1.359 1.491 1.404 1.447 1.396 σ_(n) 321 333 386 561 477 501 456 _(n)α₃ 1.742 1.685 1.934 1.754 1.556 1.905 1.769 ¹Yield % adjusted for charged and recovered dimer oligomer mixture charged. ²Examples 25 and 26 as well as Examples 27 and 28 were combined in the wash kettle before work up and isolation.

TABLE VI SASH catalyst process with initial catalyst formed from anionic polystyrene leaving a heel to form subsequent reaction mixtures. Example 29 30 31 32 33 34 35 Composite 36 Temp Catalyst Formed Rxn. 19 30 30 30 30 30 30 30 Temperature, ° C. 72 72 72 72 72 72 72 72 Atmosphere H₂ H₂ H₂ H₂ H₂ H₂ H₂ H₂ psig 30 73 73 73 73 73 73 73 CH solvent, g. 351 273 195 195 195 273 273 1404 vol, ml 450 350 250 250 250 350 350 1802 Catalyst CH Solvent, g. 85.1 85.1 86.1 88.4 90.9 92.6 92.2 535 vol, ml 109 109 110 113 117 119 118 687 Potassium t-Butoxide, g 3.63 3.63 3.67 3.77 3.88 3.96 3.94 22.86 moles 0.0324 0.0324 0.0327 0.0336 0.0346 0.0353 0.0351 0.204 Aromatic In Situ SASH SASH SASH SASH SASH SASH SASH hydrocarbon APS Heel Heel Heel Heel Heel Heel Heel Mass, g 25.00 82.00 82.00 82.00 82.00 82.00 82.00 492.00 vol, ml — 100 100 100 100 100 100 100 TMEDA, Mass, g 19.6 19.6 19.8 20.4 20.9 21.3 21.2 123.29 moles 0.169 0.169 0.171 0.175 0.180 0.184 0.183 1.06 vol, ml 25.29 25.29 25.58 26.27 27.02 27.53 27.39 159.08 n-Butyllithium, M 2.0 2.0 2.0 2.0 2.0 2.0 2.0 2.00 vol, ml 16.27 16.11 16.29 16.91 17.48 17.66 17.54 101.99 moles 0.0325 0.0322 0.0326 0.0338 0.0350 0.0353 0.0351 0.20 Monomer: styrene, g 316.4 912.4 909.9 910.8 911.2 910.8 909.0 5464.10 moles 3.04 8.76 8.74 8.75 8.75 8.75 8.73 52.46 vol, ml 348 1004 1001 1002 1002 1002 1000 6011.11 feed rate ml/min 4.93 4.93 4.93 4.93 4.93 4.93 4.93 4.93 time of feed, min 71 205 204 205 205 205 204 205 feed rate g/min 4.45 4.45 4.45 4.45 4.45 4.45 4.45 4.45 feed velocity ft/sec 5.3 5.3 5.3 5.3 5.3 5.3 5.3 5.30 Process Scale-Up Parameters mole Li/Mole K 1.005 0.995 0.995 1.005 1.010 1.002 1.000 1.00 Total Charge intial, g. 496 476 399 403 406 487 486 1526 Total Charge final, g 813 1388 1309 1313 1318 1397 1395 6990 Initial KH* concentration ppm 2628 2716 3274 3369 3450 2911 2896 5362 Final KH* concentration ppm 1605 931 998 1033 1064 1014 1009 1170 mole styrene/mole Li 93 272 268 259 250 248 249 257 mole sty/mole Li/hr 79 80 79 76 73 73 73 75 GPC SASH PS, Solvent Stripped M_(n) 351 401 423 409 482 341 380 428 M_(w) 706 637 659 626 793 511 567 663 Mz 1331 1067 1025 989 1233 865 895 1050 PD_(n) 2.01 1.59 1.56 1.53 1.65 1.50 1.49 1.55 σ_(n) 353 308 316 298 387 241 267 317 _(n)α₃ 3.53 3.24 2.64 2.87 2.46 3.71 3.01 2.83 GPC excluding Dimer Dimer Stripped M_(n) na 552 566 547 636 491 519 558 M_(w) na 760 768 733 900 655 681 763 Mz na 1126 1078 1044 1276 967 962 1100 PD_(n) na 1.38 1.36 1.34 1.42 1.33 1.31 1.37 σ_(n) na 339 338 319 410 284 290 338 _(n)α₃ na 2.93 2.41 2.71 2.22 3.24 2.84 2.66

Table VII Less Preferred SASH Catalyst Hydrogen Mediated Anionic Chain Transfer Styrene Polymerization Examples. Example 37 38 39 40 41 42 43 Rxn. Temperature, ° C. Rxn Room Rxn Rxn Rxn Rxn Rxn 72 35 72 72 72 75 90 Atmosphere H₂ H₂ H₂ H₂ H₂ H₂ H₂ psig 20 15 20 20 20 25 21-40 Solvent CH & EB EB & EB & EB & EB EB m-Xylene CH CH CH Mass, g 411.5 356 240.0 240.1 309.8 302.0 500 Aromatic Hydrocarbon, moles 1.98 3.35 1.29 0.85 2.92 2.84 4.7 Recycle M_(n) 0 0 215 199 0 0 0 Mass, g 0.00 0 98.83 93.85 0.00 0.00 0.00 moles 0.00 0.00 0.46 0.47 0.00 0.00 0.00 Alkali metal saline hydride K K NaK₂ NaK₂ Na Li Li Alkali metal alkoxide, g 3.13 4.57 3.44 3.51 2.90 2.64 3.92 moles 0.0279 0.0407 0.0318 3.0820 0.0302 0.0330 0.0489 Solvent to form alkoxide solution m-Xylene EB EB EB EB EB EB Mass, g 42.2 44 55.3 51.5 51.5 51.5 69.9 moles 0.40 0.42 0.52 0.49 0.49 0.49 0.66 vol, ml 49 51 64 59 59 59 81 TMEDA, g. 17.16 20.83 16.20 16.51 15.98 18.00 23.50 moles 0.148 0.179 0.139 0.142 0.138 0.155 0.202 vol, ml 22.14 26.88 20.90 21.30 20.62 23.23 30.33 n-Butyllithium, Molarity 2.0 2.0 2.0 2.0 2.0 2.0 2.0 vol, ml 14.81 20.34 15.91 14.40 15.63 16.50 29.62 moles 0.0296 0.0407 0.0318 0.0288 0.0313 0.0330 0.0592 Monomer: styrene, g 1000 800 1160 1000 520 338 462.2 moles 9.60 7.68 11.14 9.60 4.99 3.25 4.44 vol, ml 1100 880 1276 1100 572 372 508 feed rate ml/min 4.93 4.82 4.92 4.92 4.92 4.92 4.40 time of feed, min 225 183 261 225 117 76 116 feed rate g/min 4.45 4.38 4.44 4.44 4.44 4.44 4.00 feed velocity ft/sec 5.3 5.2 5.3 5.3 5.3 5.3 1.2 Solvent strip. polymer yield, g 1027 708 1263 1102 na na na yield % on monomer 102.7% 88.5% 100.3% 100.8% na na na M_(n) 727 648 762 637 5,713 2,593 1030 M_(w) 1135 1331 1793 1260 17,796 6,855 5635.0 Mz 1532 2490 3824 2341 28,410 10,991 10,066 PD_(n) 1.561 2.054 2.353 1.978 3.115 2.644 5.471 σ_(n) 545 665 886 630 8308 3324 2178 _(n)α₃ 1.442 3.448 4.288 3.448 2.648 2.503 4.131 Dimer strip. polymer yield, g 977.14 629.5 1140 970.6 na na na yield % on monomer 98% 79% 98% 97% na na na M_(n) 805 816 na 605 na 2375* na M_(w) 1169 1364 na 1270 na 6887 na Mz 1535 2222 na 2431 na 11071 na PD_(n) 1.452 1.672 na 2.099 na 2.900 na σ_(n) 541 669 na 634 na 3274 na _(n)α₃ 1.357 2.793 na 3.590 na 2.604 na *Small portion stripped of solvent in a Kugelrohr short path distillation apparatus.

TABLE VIII SASH PS catalyzed process w/ more uniform hydrogen transfer to condensed phase, w/ recycle and with high velocity feed. Example 44 45 46 47 48 49 50 51 Temp Catalyst Formed 20 20 20 20 20 20 20 20 Temperature, ° C. 73 73 73 73 73 73 73 73 Atmosphere H₂ H₂ H₂ H₂ H₂ H₂ H₂ H₂ psig 20 20 20 20 20 20 20 20 Ethylbenzene, g. 219.8 219.8 288.8 281.2 281.2 281.2 273.1 273.1 mole 2.07 2.07 2.72 2.65 2.65 2.65 2.57 2.57 vol, ml 253 253 333 324 324 324 315 315 Dimer M_(n) 227 227 227 227 210 210 210 210 Mass, g. 108.24 108.24 61.25 59.64 59.64 59.64 57.93 57.93 mole 0.48 0.48 0.27 0.26 0.28 0.28 0.28 0.28 vol, ml 116 116 66 64 64 64 113 113 Potassium t-butoxide 3.86 3.82 3.80 3.59 2.96 2.99 2.95 2.85 mole 0.0344 0.0340 0.0338 0.0320 0.0264 0.0266 0.0263 0.0254 Etyhylbenzene, g. 67.7 68.1 66.9 63.9 51.8 53.2 52.6 50.8 mole 0.64 0.64 0.63 0.60 0.49 0.50 0.50 0.48 vol, ml 78 79 77 74 60 61 61 59 TMEDA, g. 18.14 17.95 17.47 16.86 13.54 14.03 13.86 13.39 mole 0.156 0.154 0.150 0.145 0.117 0.121 0.119 0.115 vol, ml 23.40 23.16 22.55 21.75 17.47 18.11 17.88 17.28 n-Butyllithium, M 2.0 2.0 2.0 2.0 2.0 2.0 2.0 2.0 vol, ml 18.06 17.26 17.76 16.10 13.28 13.61 13.48 12.71 mole 0.0361 0.0345 0.0355 0.0322 0.0266 0.0272 0.0270 0.0254 Monomer: styrene, g. 1124.4 1060.6 1054.4 1058 1058 1055.1 1053.8 1052.4 mole 10.80 10.18 10.12 10.16 10.16 10.13 10.12 10.10 vol, ml 1237 1167 1160 1164 1164 1161 1159 1158 feed rate ml/min 6.2 6.2 6.2 6.2 5.0 5.0 5.0 5.0 time of feed, min 200 188 187 188 233 232 232 232 feed rate g/min 5.64 5.64 5.64 5.64 4.55 4.55 4.55 4.55 feed velocity ft/s 13.7 13.7 13.7 13.7 11.0 11.0 11.0 11.0 ProcessScale-Up Parameters mole lithium/mole potassium 1.05 1.01 1.05 1.01 1.01 1.02 1.03 1.00 Mole TMEDA/mole alkali 2.21 2.25 2.17 2.26 2.20 2.24 2.24 2.27 Total Charge initial, g. 432 431 452 438 419 422 411 408 Total Charge final, g. 1556 1492 1506 1496 1477 1477 1465 1460 Initial KH* conc. ppm 3355 3210 3152 2951 2540 2590 2633 2500 Final KH* conc. ppm 931 928 946 863 721 739 739 698 mole styrene/mole Li 299 295 285 316 383 372 375 397 mole sty/mole Li/hr 90 94 91 101 99 96 97 103 mole sty./mole Org. CTA 3.39 3.19 2.80 2.89 2.97 2.95 3.03 3.04 mole sty./hr/mole Org. CTA 1.02 1.02 0.90 0.92 0.77 0.76 0.78 0.79 GPC MWD trimer and above M_(n) 698 570 605 550 589 576 559 634 M_(w) 993 745 799 710 773 747 721 865 Mz 1355 985 1053 930 1013 972 940 1163 PD_(n) 1.423 1.307 1.321 1.291 1.312 1.297 1.290 1.364 σ_(n) 454 316 343 297 329 314 301 383 _(n)α₃ 2.067 2.087 2.075 2.085 2.072 2.072 2.079 2.077 EB Strip. SASH PS, g. 2064.9 2004.3 2025.3 1991.0 polymer yield %, g 86% 90% 91% 90% Dimer strip. polymer yield, g 1671 1609 1639 1611 yield % on monomer 76% 76% 78% 77% M_(n) 613 586 610 599 M_(w) 824 766 794 799 Mz 1102 999 1038 1057 PD_(n) 1.34 1.31 1.30 1.33 σ_(n) 360 325 335 346 _(n)α₃ 1.90 1.80 1.87 1.83

TABLE IX SASH catalyzed process w/ uniform hydrogen transfer to condensed phase, w/ or w/o recycle and with low velocity feed Example 52 53 54 55 56 57 58 59 60 Temp Catalyst Formed Rxn Rxn Rxn Rxn Rxn Rxn Rxn Rxn Rxn Temperature, ° C. 78 80 80 80 85 90 90 90 90 Atmosphere H₂ H₂ H₂ H₂ H₂ H₂ H₂ H₂ H₂ psig 15 15 18 18 21 21 21 21 21 Ethylbenzene, g. 188.6 188.0 290.9 308.3 303.2 296.8 433.5 434.2 422.1 mole 1.78 1.77 2.74 2.90 2.86 2.80 4.08 4.09 3.98 vol, ml 218 217 336 356 350 342 500 501 487 Dimer M_(n) 227 227 227 227 227 227 na na na Mass, g 125.39 124.98 142.97 134.67 149.33 146.19 0.00 0.00 0.00 mole 0.55 0.55 0.63 0.59 0.66 0.64 0.00 0.00 0.00 vol, ml 135 134 154 145 161 157 0 0 0 Potassium t-butoxide 3.94 3.90 4.01 3.88 3.79 3.52 3.66 3.70 3.75 mole 0.0351 0.0347 0.0357 0.0346 0.0338 0.0314 0.0326 0.0330 0.0334 Ethylbenzene, g 69.2 68.6 69.9 67.8 66.2 61.4 68.2 69.0 69.9 mole 0.65 0.65 0.66 0.64 0.62 0.58 0.64 0.65 0.66 vol, ml 80 79 81 78 76 71 79 80 81 TMEDA, g 18.53 17.93 19.90 19.29 18.83 17.47 17.48 17.67 17.90 mole 0.159 0.154 0.171 0.166 0.162 0.150 0.150 0.152 0.154 vol, ml 23.91 23.14 25.68 24.89 24.30 22.55 22.55 22.80 23.09 n-Butyllithium, M 2.0 2.0 2.0 2.0 2.0 2.0 2.0 2.0 2.0 vol, ml 18.44 18.40 18.91 18.67 18.67 17.42 18.43 19.65 21.88 mole 0.0369 0.0368 0.0378 0.0373 0.0373 0.0348 0.0369 0.0393 0.0438 Total mass, g 14.32 14.29 14.68 14.50 14.50 13.53 14.31 15.26 16.99 neat mass, g 2.3628 2.358 2.4222 2.3925 2.3925 2.23245 2.36115 2.5179 2.80335 Monomer: styrene, g 1141.5 1151.6 1038.8 1032.6 1030.2 1017.8 1037.8 1041.3 1044.9 mole 10.96 11.06 9.97 9.91 9.89 9.77 9.96 10.00 10.03 vol, ml 1256 1267 1143 1136 1133 1120 1142 1146 1150 feed rate ml/min 6.9 6.95 7 7 7.35 7.35 7.5 7.5 7.5 time of feed, min 182 182 163 162 154 152 152 153 153 feed rate g/min 6.27 6.32 6.36 6.36 6.68 6.68 6.82 6.82 6.82 feed velocity ft/s 1.88 1.88 1.88 1.88 1.98 1.98 2.02 2.02 2.02 Process Scale-Up Parameters mole lithium/mole potassium 1.05 1.06 1.06 1.08 1.11 1.11 1.13 1.19 1.31 Mole TMEDA/mole alkali 2.21 2.16 2.33 2.31 2.28 2.27 2.16 2.10 2.00 Total Charge intial, g. 420 418 542 548 556 539 537 540 531 Total Charge final, g 1562 1569 1581 1581 1586 1557 1575 1581 1576 Initial KH* conc. ppm 3522 3534 2796 2731 2695 2594 2752 2920 3308 Final KH* conc. ppm 947 941 959 947 945 898 939 997 1114 mole styrene/mole Li 297 300 264 265 265 280 270 254 229 mole sty/mole Li/hr 98 99 97 98 103 110 107 100 90 mole sty./mole Org. CTA 3.68 3.72 2.48 2.40 2.39 2.43 2.11 2.11 2.16 mole styr/hr/mole Org. CTA 1.21 1.23 0.91 0.89 0.93 0.96 0.83 0.83 0.85 GPC MWD trimer and above M_(n) 822 732 533 555 595 566 668 656 590 M_(w) 1186 1031 681 722 794 756 908 904 795 Mz 1571 1377 892 961 1072 1059 1213 1232 1103 PD_(n) 1.443 1.408 1.278 1.301 1.334 1.336 1.522 1.546 1.515 σ_(n) 547 468 281 304 344 328 400 401 340 _(n)α₃ 1.456 1.625 2.086 2.120 2.073 2.530 1.813 1.953 2.327 EB Strip. SASH PS, g. 2476.8 2299.8 2340.0 2160.8 1100.040 polymer yield %, g 97% 98% 100% 104% 105% Dimer strip. polymer yield, g 2160 1790 1869 1933 932.01 yield % on monomer 99% 87% 91% 93% 89% M_(n) 776 559 549 665 605 M_(w) 1110 719 762 911 812 Mz 1476 941 1053 1226 1119 PDn 1.43 1.29 1.39 1.37 1.34 σ_(n) 509 299 342 404 354 _(n)α₃ 1.52 2.00 2.06 1.85 2.28 

What is claimed:
 1. A process for anionic chain transfer polymerization comprising feeding a vinyl aromatic and/or conjugated diene monomer under an atmosphere comprising molecular hydrogen to a reactor vessel containing a reaction mixture of an inert ethereal solvent and an alkali metal or alkali metal alloy.
 2. The process of claim 1, wherein said vinyl aromatic monomer is a styrenic monomer.
 3. The process of claim 1, wherein the reaction mixture further comprises an electron transfer entraining agent.
 4. The process of claim 1, wherein the ethereal solvent and alkali metal or alkali metal alloy are initially charged into the reactor vessel and agitated using high shear mixing to create a dispersion of the initially charged alkali metal or alkali metal alloy.
 5. The process of claim 1, wherein the partial pressure of hydrogen is maintained at pressures between about 1.0 Bar to about 20 Bar.
 6. The process of claim 1, wherein the alkali metal alloy is comprised of sodium and potassium.
 7. The process of claim 1 wherein the molar ratio of g-atom alkali metal or alkali metal alloy to styrenic monomer is in the range of about 1:10 to about 1:100.
 8. The process of claim 1 where the vinyl aromatic monomer is styrene, the ethereal solvent is tetrahydrofuran and the sodium potassium alloy is NaK₂.
 9. The process of claim 1 where the vinyl aromatic monomer is styrene, the ethereal solvent is tetrahydrofuran, the sodium potassium alloy is NaK₂ and the partial pressure of hydrogen is maintained at pressures between about 2.5 Bar to about 10 Bar. 